CGI::HTML::Functions(3)                    User Contributed Perl Documentation


NAME
       CGI::HTML::Functions - Documentation for CGI.pm Legacy HTML
       Functionality

SYNOPSIS
       Nothing here - please do not use this functionality, it is considered
       to be legacy and essentially deprecated. This documentation exists
       solely to aid in maintenance and migration of legacy code using this
       functionality and you are strongly encouraged to migrate away from it.
       If you are working on new code you should be using a template engine.
       For more information see CGI::Alternatives.

       If you really want to continue using the HTML generation functionality
       of CGI.pm then you should take a look at HTML::Tiny instead, which may
       give you a migration path away from CGI.pm's html generation functions;
       i strongly encourage you to move towards template driven page
       generation for anything involving markup as it will make porting your
       app to other frameworks much easier in the long run.

DESCRIPTION
       The documentation here should be considered an addendum to the sections
       in the CGI documentation - the sections here are named the same as
       those within the CGI perldoc.

Calling CGI.pm routines
       HTML tag functions have both attributes (the attribute="value" pairs
       within the tag itself) and contents (the part between the opening and
       closing pairs). To distinguish between attributes and contents, CGI.pm
       uses the convention of passing HTML attributes as a hash reference as
       the first argument, and the contents, if any, as any subsequent
       arguments.  It works out like this:

           Code                           Generated HTML
           ----                           --------------
           h1()                           <h1 />
           h1('some','contents');         <h1>some contents</h1>
           h1({-align=>left});            <h1 align="LEFT">
           h1({-align=>left},'contents'); <h1 align="LEFT">contents</h1>

       Many newcomers to CGI.pm are puzzled by the difference between the
       calling conventions for the HTML shortcuts, which require curly braces
       around the HTML tag attributes, and the calling conventions for other
       routines, which manage to generate attributes without the curly
       brackets. Don't be confused. As a convenience the curly braces are
       optional in all but the HTML shortcuts. If you like, you can use curly
       braces when calling any routine that takes named arguments. For
       example:

           print $q->header( { -type => 'image/gif', -expires => '+3d' } );

       If you use warnings, you will be warned that some CGI.pm argument names
       conflict with built-in perl functions. The most frequent of these is
       the -values argument, used to create multi-valued menus, radio button
       clusters and the like. To get around this warning, you have several
       choices:

       1.  Use another name for the argument, if one is available.  For
           example, -value is an alias for -values.

       2.  Change the capitalization, e.g. -Values

       3.  Put quotes around the argument name, e.g. '-values'

   Function-oriented interface HTML exports
       Here is a list of the HTML related function sets you can import:

       :form
           Import all fill-out form generating methods, such as textfield().

       :html2
           Import all methods that generate HTML 2.0 standard elements.

       :html3
           Import all methods that generate HTML 3.0 elements (such as
           <table>, <super> and <sub>).

       :html4
           Import all methods that generate HTML 4 elements (such as <abbrev>,
           <acronym> and <thead>).

       :netscape
           Import the <blink>, <fontsize> and <center> tags.

       :html
           Import all HTML-generating shortcuts (i.e. 'html2', 'html3',
           'html4' and 'netscape')

       :standard
           Import "standard" features, 'html2', 'html3', 'html4', 'ssl',
           'form' and 'cgi'.

       If you import any of the state-maintaining CGI or form-generating
       methods, a default CGI object will be created and initialized
       automatically the first time you use any of the methods that require
       one to be present. This includes param(), textfield(), submit() and the
       like. (If you need direct access to the CGI object, you can find it in
       the global variable $CGI::Q).

   Pragmas
       Additional HTML generation related pragms:

       -nosticky
           By default the CGI module implements a state-preserving behavior
           called "sticky" fields. The way this works is that if you are
           regenerating a form, the methods that generate the form field
           values will interrogate param() to see if similarly-named
           parameters are present in the query string. If they find a like-
           named parameter, they will use it to set their default values.

           Sometimes this isn't what you want. The -nosticky pragma prevents
           this behavior. You can also selectively change the sticky behavior
           in each element that you generate.

       -tabindex
           Automatically add tab index attributes to each form field. With
           this option turned off, you can still add tab indexes manually by
           passing a -tabindex option to each field-generating method.

       -no_xhtml
           By default, CGI.pm versions 2.69 and higher emit XHTML
           (http://www.w3.org/TR/xhtml1/). The -no_xhtml pragma disables this
           feature.  Thanks to Michalis Kabrianis <kabrianis@hellug.gr> for
           this feature.

           If start_html()'s -dtd parameter specifies an HTML 2.0, 3.2, 4.0 or
           4.01 DTD, XHTML will automatically be disabled without needing to
           use this pragma.

   Special forms for importing HTML-tag functions
       Many of the methods generate HTML tags. As described below, tag
       functions automatically generate both the opening and closing tags. For
       example:

           print h1('Level 1 Header');

       produces

           <h1>Level 1 Header</h1>

       There will be some times when you want to produce the start and end
       tags yourself. In this case, you can use the form start_tag_name and
       end_tag_name, as in:

           print start_h1,'Level 1 Header',end_h1;

   Creating the HTML document header
           print start_html(
               -title      => 'Secrets of the Pyramids',
               -author     => 'fred@capricorn.org',
               -base       => 'true',
               -target     => '_blank',
               -meta       => {'keywords'=>'pharaoh secret mummy',
               'copyright' => 'copyright 1996 King Tut'},
               -style      => {'src'=>'/styles/style1.css'},
               -BGCOLOR    => 'blue'
           );

       The start_html() routine creates the top of the page, along with a lot
       of optional information that controls the page's appearance and
       behavior.

       This method returns a canned HTML header and the opening <body> tag.
       All parameters are optional. In the named parameter form, recognized
       parameters are -title, -author, -base, -xbase, -dtd, -lang and -target
       (see below for the explanation). Any additional parameters you provide,
       such as the unofficial BGCOLOR attribute, are added to the <body> tag.
       Additional parameters must be proceeded by a hyphen.

       The argument -xbase allows you to provide an HREF for the <base> tag
       different from the current location, as in

           -xbase => "http://home.mcom.com/"

       All relative links will be interpreted relative to this tag.

       The argument -target allows you to provide a default target frame for
       all the links and fill-out forms on the page. This is a non-standard
       HTTP feature which only works with some browsers!

           -target => "answer_window"

       All relative links will be interpreted relative to this tag.  You add
       arbitrary meta information to the header with the -meta argument. This
       argument expects a reference to a hash containing name/value pairs of
       meta information. These will be turned into a series of header <meta>
       tags that look something like this:

           <meta name="keywords" content="pharaoh secret mummy">
           <meta name="description" content="copyright 1996 King Tut">

       To create an HTTP-EQUIV type of <meta> tag, use -head, described below.

       The -style argument is used to incorporate cascading stylesheets into
       your code. See the section on CASCADING STYLESHEETS for more
       information.

       The -lang argument is used to incorporate a language attribute into the
       <html> tag. For example:

           print $q->start_html( -lang => 'fr-CA' );

       The default if not specified is "en-US" for US English, unless the -dtd
       parameter specifies an HTML 2.0 or 3.2 DTD, in which case the lang
       attribute is left off.  You can force the lang attribute to left off in
       other cases by passing an empty string (-lang=>'').

       The -encoding argument can be used to specify the character set for
       XHTML. It defaults to iso-8859-1 if not specified.

       The -dtd argument can be used to specify a public DTD identifier
       string. For example:

           -dtd => '-//W3C//DTD HTML 4.01 Transitional//EN')

       Alternatively, it can take public and system DTD identifiers as an
       array:

           -dtd => [
               '-//W3C//DTD HTML 4.01 Transitional//EN',
               'http://www.w3.org/TR/html4/loose.dtd'
           ]

       For the public DTD identifier to be considered, it must be valid.
       Otherwise it will be replaced by the default DTD. If the public DTD
       contains 'XHTML', CGI.pm will emit XML.

       The -declare_xml argument, when used in conjunction with XHTML, will
       put a <?xml> declaration at the top of the HTML header. The sole
       purpose of this declaration is to declare the character set encoding.
       In the absence of -declare_xml, the output HTML will contain a <meta>
       tag that specifies the encoding, allowing the HTML to pass most
       validators. The default for -declare_xml is false.

       You can place other arbitrary HTML elements to the <head> section with
       the -head tag.  For example, to place a <link> element in the head
       section, use this:

           print start_html(
               -head => Link({
                   -rel  => 'shortcut icon',
                   -href => 'favicon.ico'
               })
           );

       To incorporate multiple HTML elements into the <head> section, just
       pass an array reference:

           print start_html(
               -head => [
                   Link({
                       -rel  => 'next',
                       -href => 'http://www.capricorn.com/s2.html'
                   }),
                   Link({
                       -rel  => 'previous',
                       -href => 'http://www.capricorn.com/s1.html'
                   })
               ]
           );

       And here's how to create an HTTP-EQUIV <meta> tag:

           print start_html(
               -head => meta({
                   -http_equiv => 'Content-Type',
                   -content    => 'text/html'
               })
           );

       JAVASCRIPTING: The -script, -noScript, -onLoad, -onMouseOver,
       -onMouseOut and -onUnload parameters are used to add JavaScript calls
       to your pages. -script should point to a block of text containing
       JavaScript function definitions. This block will be placed within a
       <script> block inside the HTML (not HTTP) header. The block is placed
       in the header in order to give your page a fighting chance of having
       all its JavaScript functions in place even if the user presses the stop
       button before the page has loaded completely. CGI.pm attempts to format
       the script in such a way that JavaScript-naive browsers will not choke
       on the code: unfortunately there are some browsers that get confused by
       it nevertheless.

       The -onLoad and -onUnload parameters point to fragments of JavaScript
       code to execute when the page is respectively opened and closed by the
       browser.  Usually these parameters are calls to functions defined in
       the -script field:

           $q = CGI->new;
           print header;
           $JSCRIPT = <<END;
               // Ask a silly question
               function riddle_me_this() {
                   var r = prompt(
                       "What walks on four legs in the morning, " +
                       "two legs in the afternoon, " +
                       "and three legs in the evening?"
                   );
                   response(r);
               }
               // Get a silly answer
               function response(answer) {
                   if (answer == "man")
                       alert("Right you are!");
                   else
                       alert("Wrong!  Guess again.");
               }
           END
           print start_html(
               -title  => 'The Riddle of the Sphinx',
               -script => $JSCRIPT
           );

       Use the -noScript parameter to pass some HTML text that will be
       displayed on browsers that do not have JavaScript (or browsers where
       JavaScript is turned off).

       The <script> tag, has several attributes including "type", "charset"
       and "src".  "src" allows you to keep JavaScript code in an external
       file. To use these attributes pass a HASH reference in the -script
       parameter containing one or more of -type, -src, or -code:

           print $q->start_html(
               -title  => 'The Riddle of the Sphinx',
               -script => {
                   -type => 'JAVASCRIPT',
                   -src  => '/javascript/sphinx.js'}
               );

           print $q->(
               -title  => 'The Riddle of the Sphinx',
               -script => {
                   -type => 'PERLSCRIPT',
                   -code => 'print "hello world!\n;"'
               }
           );

       A final feature allows you to incorporate multiple <script> sections
       into the header. Just pass the list of script sections as an array
       reference. This allows you to specify different source files for
       different dialects of JavaScript.  Example:

           print $q->start_html(
               -title  => 'The Riddle of the Sphinx',
               -script => [
                   {
                       -type => 'text/javascript',
                       -src  => '/javascript/utilities10.js'
                   },
                   {
                       -type => 'text/javascript',
                       -src  => '/javascript/utilities11.js'
                   },
                   {
                       -type => 'text/jscript',
                       -src  => '/javascript/utilities12.js'
                   },
                   {
                       -type => 'text/ecmascript',
                       -src  => '/javascript/utilities219.js'
                   }
               ]
           );

       The option "-language" is a synonym for -type, and is supported for
       backwards compatibility.

       The old-style positional parameters are as follows:

       Parameters:

       1.  The title

       2.  The author's e-mail address (will create a <link rev="MADE"> tag if
           present

       3.  A 'true' flag if you want to include a <base> tag in the header.
           This helps resolve relative addresses to absolute ones when the
           document is moved, but makes the document hierarchy non-portable.
           Use with care!

       Other parameters you want to include in the <body> tag may be appended
       to these.  This is a good place to put HTML extensions, such as colors
       and wallpaper patterns.

   Ending the Html document:
           print $q->end_html;

       This ends an HTML document by printing the </body></html> tags.

CREATING STANDARD HTML ELEMENTS:
       CGI.pm defines general HTML shortcut methods for many HTML tags.  HTML
       shortcuts are named after a single HTML element and return a fragment
       of HTML text. Example:

          print $q->blockquote(
                            "Many years ago on the island of",
                            $q->a({href=>"http://crete.org/"},"Crete"),
                            "there lived a Minotaur named",
                            $q->strong("Fred."),
                           ),
              $q->hr;

       This results in the following HTML code (extra newlines have been added
       for readability):

          <blockquote>
          Many years ago on the island of
          <a href="http://crete.org/">Crete</a> there lived
          a minotaur named <strong>Fred.</strong>
          </blockquote>
          <hr>

       If you find the syntax for calling the HTML shortcuts awkward, you can
       import them into your namespace and dispense with the object syntax
       completely (see the next section for more details):

          use CGI ':standard';
          print blockquote(
             "Many years ago on the island of",
             a({href=>"http://crete.org/"},"Crete"),
             "there lived a minotaur named",
             strong("Fred."),
             ),
             hr;

   Providing arguments to HTML shortcuts
       The HTML methods will accept zero, one or multiple arguments.  If you
       provide no arguments, you get a single tag:

          print hr;    #  <hr>

       If you provide one or more string arguments, they are concatenated
       together with spaces and placed between opening and closing tags:

          print h1("Chapter","1"); # <h1>Chapter 1</h1>"

       If the first argument is a hash reference, then the keys and values of
       the hash become the HTML tag's attributes:

          print a({-href=>'fred.html',-target=>'_new'},
             "Open a new frame");

                   <a href="fred.html",target="_new">Open a new frame</a>

       You may dispense with the dashes in front of the attribute names if you
       prefer:

          print img {src=>'fred.gif',align=>'LEFT'};

                  <img align="LEFT" src="fred.gif">

       Sometimes an HTML tag attribute has no argument.  For example, ordered
       lists can be marked as COMPACT.  The syntax for this is an argument
       that that points to an undef string:

          print ol({compact=>undef},li('one'),li('two'),li('three'));

       Prior to CGI.pm version 2.41, providing an empty ('') string as an
       attribute argument was the same as providing undef.  However, this has
       changed in order to accommodate those who want to create tags of the
       form <img alt="">.  The difference is shown in these two pieces of
       code:

          CODE                   RESULT
          img({alt=>undef})      <img alt>
          img({alt=>''})         <img alt="">

   The distributive property of HTML shortcuts
       One of the cool features of the HTML shortcuts is that they are
       distributive.  If you give them an argument consisting of a reference
       to a list, the tag will be distributed across each element of the list.
       For example, here's one way to make an ordered list:

          print ul(
                    li({-type=>'disc'},['Sneezy','Doc','Sleepy','Happy'])
                  );

       This example will result in HTML output that looks like this:

          <ul>
            <li type="disc">Sneezy</li>
            <li type="disc">Doc</li>
            <li type="disc">Sleepy</li>
            <li type="disc">Happy</li>
          </ul>

       This is extremely useful for creating tables.  For example:

          print table({-border=>undef},
                  caption('When Should You Eat Your Vegetables?'),
                  Tr({-align=>'CENTER',-valign=>'TOP'},
                  [
                     th(['Vegetable', 'Breakfast','Lunch','Dinner']),
                     td(['Tomatoes' , 'no', 'yes', 'yes']),
                     td(['Broccoli' , 'no', 'no',  'yes']),
                     td(['Onions'   , 'yes','yes', 'yes'])
                  ]
                  )
               );

   HTML shortcuts and list interpolation
       Consider this bit of code:

          print blockquote(em('Hi'),'mom!'));

       It will ordinarily return the string that you probably expect, namely:

          <blockquote><em>Hi</em> mom!</blockquote>

       Note the space between the element "Hi" and the element "mom!".  CGI.pm
       puts the extra space there using array interpolation, which is
       controlled by the magic $" variable.  Sometimes this extra space is not
       what you want, for example, when you are trying to align a series of
       images.  In this case, you can simply change the value of $" to an
       empty string.

          {
             local($") = '';
             print blockquote(em('Hi'),'mom!'));
           }

       I suggest you put the code in a block as shown here.  Otherwise the
       change to $" will affect all subsequent code until you explicitly reset
       it.

   Non-standard HTML shortcuts
       A few HTML tags don't follow the standard pattern for various reasons.

       comment() generates an HTML comment (<!-- comment -->).  Call it like

           print comment('here is my comment');

       Because of conflicts with built-in perl functions, the following
       functions begin with initial caps:

           Select
           Tr
           Link
           Delete
           Accept
           Sub

       In addition, start_html(), end_html(), start_form(), end_form(),
       start_multipart_form() and all the fill-out form tags are special.  See
       their respective sections.

   Autoescaping HTML
       By default, all HTML that is emitted by the form-generating functions
       is passed through a function called escapeHTML():

       $escaped_string = escapeHTML("unescaped string");
           Escape HTML formatting characters in a string. Internally this
           calls HTML::Entities (encode_entities) so really you should just
           use that instead - the default list of chars that will be encoded
           (passed to the HTML::Entities encode_entities method) is:

               & < > " \x8b \x9b '

           you can control this list by setting the value of
           $CGI::ENCODE_ENTITIES:

               # only encode < >
               $CGI::ENCODE_ENTITIES = q{<>}

           if you want to encode all entities then undef
           $CGI::ENCODE_ENTITIES:

               # encode all entities
               $CGI::ENCODE_ENTITIES = undef;

       The automatic escaping does not apply to other shortcuts, such as h1().
       You should call escapeHTML() yourself on untrusted data in order to
       protect your pages against nasty tricks that people may enter into
       guestbooks, etc..  To change the character set, use charset().  To turn
       autoescaping off completely, use autoEscape(0):

       $charset = charset([$charset]);
           Get or set the current character set.

       $flag = autoEscape([$flag]);
           Get or set the value of the autoescape flag.

CREATING FILL-OUT FORMS:
       General note  The various form-creating methods all return strings to
       the caller, containing the tag or tags that will create the requested
       form element.  You are responsible for actually printing out these
       strings.  It's set up this way so that you can place formatting tags
       around the form elements.

       Another note The default values that you specify for the forms are only
       used the first time the script is invoked (when there is no query
       string).  On subsequent invocations of the script (when there is a
       query string), the former values are used even if they are blank.

       If you want to change the value of a field from its previous value, you
       have two choices:

       (1) call the param() method to set it.

       (2) use the -override (alias -force) parameter (a new feature in
       version 2.15).  This forces the default value to be used, regardless of
       the previous value:

          print textfield(-name=>'field_name',
                                  -default=>'starting value',
                                  -override=>1,
                                  -size=>50,
                                  -maxlength=>80);

       Yet another note By default, the text and labels of form elements are
       escaped according to HTML rules.  This means that you can safely use
       "<CLICK ME>" as the label for a button.  However, it also interferes
       with your ability to incorporate special HTML character sequences, such
       as &Aacute;, into your fields.  If you wish to turn off automatic
       escaping, call the autoEscape() method with a false value immediately
       after creating the CGI object:

          $q = CGI->new;
          $q->autoEscape(0);

       Note that autoEscape() is exclusively used to effect the behavior of
       how some CGI.pm HTML generation functions handle escaping. Calling
       escapeHTML() explicitly will always escape the HTML.

       A Lurking Trap! Some of the form-element generating methods return
       multiple tags.  In a scalar context, the tags will be concatenated
       together with spaces, or whatever is the current value of the $"
       global.  In a list context, the methods will return a list of elements,
       allowing you to modify them if you wish.  Usually you will not notice
       this behavior, but beware of this:

           printf("%s\n",end_form())

       end_form() produces several tags, and only the first of them will be
       printed because the format only expects one value.

       <p>

   Creating an isindex tag
          print isindex(-action=>$action);

                -or-

          print isindex($action);

       Prints out an <isindex> tag.  Not very exciting.  The parameter -action
       specifies the URL of the script to process the query.  The default is
       to process the query with the current script.

   Starting and ending a form
           print start_form(-method=>$method,
                           -action=>$action,
                           -enctype=>$encoding);
             <... various form stuff ...>
           print end_form;

               -or-

           print start_form($method,$action,$encoding);
             <... various form stuff ...>
           print end_form;

       start_form() will return a <form> tag with the optional method, action
       and form encoding that you specify.  The defaults are:

           method: POST
           action: this script
           enctype: application/x-www-form-urlencoded for non-XHTML
                    multipart/form-data for XHTML, see multipart/form-data below.

       end_form() returns the closing </form> tag.

       start_form()'s enctype argument tells the browser how to package the
       various fields of the form before sending the form to the server.  Two
       values are possible:

       application/x-www-form-urlencoded
           This is the older type of encoding.  It is compatible with many CGI
           scripts and is suitable for short fields containing text data.  For
           your convenience, CGI.pm stores the name of this encoding type in
           &CGI::URL_ENCODED.

       multipart/form-data
           This is the newer type of encoding.  It is suitable for forms that
           contain very large fields or that are intended for transferring
           binary data.  Most importantly, it enables the "file upload"
           feature.  For your convenience, CGI.pm stores the name of this
           encoding type in &CGI::MULTIPART

           Forms that use this type of encoding are not easily interpreted by
           CGI scripts unless they use CGI.pm or another library designed to
           handle them.

           If XHTML is activated (the default), then forms will be
           automatically created using this type of encoding.

       The start_form() method uses the older form of encoding by default
       unless XHTML is requested.  If you want to use the newer form of
       encoding by default, you can call start_multipart_form() instead of
       start_form().  The method end_multipart_form() is an alias to
       end_form().

       JAVASCRIPTING: The -name and -onSubmit parameters are provided for use
       with JavaScript.  The -name parameter gives the form a name so that it
       can be identified and manipulated by JavaScript functions.  -onSubmit
       should point to a JavaScript function that will be executed just before
       the form is submitted to your server.  You can use this opportunity to
       check the contents of the form for consistency and completeness.  If
       you find something wrong, you can put up an alert box or maybe fix
       things up yourself.  You can abort the submission by returning false
       from this function.

       Usually the bulk of JavaScript functions are defined in a <script>
       block in the HTML header and -onSubmit points to one of these function
       call.  See start_html() for details.

   Form elements
       After starting a form, you will typically create one or more
       textfields, popup menus, radio groups and other form elements.  Each of
       these elements takes a standard set of named arguments.  Some elements
       also have optional arguments.  The standard arguments are as follows:

       -name
           The name of the field. After submission this name can be used to
           retrieve the field's value using the param() method.

       -value, -values
           The initial value of the field which will be returned to the script
           after form submission.  Some form elements, such as text fields,
           take a single scalar -value argument. Others, such as popup menus,
           take a reference to an array of values. The two arguments are
           synonyms.

       -tabindex
           A numeric value that sets the order in which the form element
           receives focus when the user presses the tab key. Elements with
           lower values receive focus first.

       -id A string identifier that can be used to identify this element to
           JavaScript and DHTML.

       -override
           A boolean, which, if true, forces the element to take on the value
           specified by -value, overriding the sticky behavior described
           earlier for the -nosticky pragma.

       -onChange, -onFocus, -onBlur, -onMouseOver, -onMouseOut, -onSelect
           These are used to assign JavaScript event handlers. See the
           JavaScripting section for more details.

       Other common arguments are described in the next section. In addition
       to these, all attributes described in the HTML specifications are
       supported.

   Creating a text field
           print textfield(-name=>'field_name',
                           -value=>'starting value',
                           -size=>50,
                           -maxlength=>80);
               -or-

           print textfield('field_name','starting value',50,80);

       textfield() will return a text input field.

       Parameters

       1.  The first parameter is the required name for the field (-name).

       2.  The optional second parameter is the default starting value for the
           field contents (-value, formerly known as -default).

       3.  The optional third parameter is the size of the field in
                 characters (-size).

       4.  The optional fourth parameter is the maximum number of characters
           the
                 field will accept (-maxlength).

       As with all these methods, the field will be initialized with its
       previous contents from earlier invocations of the script.  When the
       form is processed, the value of the text field can be retrieved with:

              $value = param('foo');

       If you want to reset it from its initial value after the script has
       been called once, you can do so like this:

              param('foo',"I'm taking over this value!");

   Creating a big text field
          print textarea(-name=>'foo',
                                 -default=>'starting value',
                                 -rows=>10,
                                 -columns=>50);

               -or

          print textarea('foo','starting value',10,50);

       textarea() is just like textfield, but it allows you to specify rows
       and columns for a multiline text entry box.  You can provide a starting
       value for the field, which can be long and contain multiple lines.

   Creating a password field
          print password_field(-name=>'secret',
                                       -value=>'starting value',
                                       -size=>50,
                                       -maxlength=>80);
               -or-

          print password_field('secret','starting value',50,80);

       password_field() is identical to textfield(), except that its contents
       will be starred out on the web page.

   Creating a file upload field
           print filefield(-name=>'uploaded_file',
                                   -default=>'starting value',
                                   -size=>50,
                                   -maxlength=>80);
               -or-

           print filefield('uploaded_file','starting value',50,80);

       filefield() will return a file upload field.  In order to take full
       advantage of this you must use the new multipart encoding scheme for
       the form.  You can do this either by calling start_form() with an
       encoding type of &CGI::MULTIPART, or by calling the new method
       start_multipart_form() instead of vanilla start_form().

       Parameters

       1.  The first parameter is the required name for the field (-name).

       2.  The optional second parameter is the starting value for the field
           contents to be used as the default file name (-default).

           For security reasons, browsers don't pay any attention to this
           field, and so the starting value will always be blank.  Worse, the
           field loses its "sticky" behavior and forgets its previous
           contents.  The starting value field is called for in the HTML
           specification, however, and possibly some browser will eventually
           provide support for it.

       3.  The optional third parameter is the size of the field in characters
           (-size).

       4.  The optional fourth parameter is the maximum number of characters
           the field will accept (-maxlength).

       JAVASCRIPTING: The -onChange, -onFocus, -onBlur, -onMouseOver,
       -onMouseOut and -onSelect parameters are recognized.  See textfield()
       for details.

   Creating a popup menu
          print popup_menu('menu_name',
                                   ['eenie','meenie','minie'],
                                   'meenie');

             -or-

          %labels = ('eenie'=>'your first choice',
                     'meenie'=>'your second choice',
                     'minie'=>'your third choice');
          %attributes = ('eenie'=>{'class'=>'class of first choice'});
          print popup_menu('menu_name',
                                   ['eenie','meenie','minie'],
                 'meenie',\%labels,\%attributes);

               -or (named parameter style)-

          print popup_menu(-name=>'menu_name',
                                   -values=>['eenie','meenie','minie'],
                                   -default=>['meenie','minie'],
                 -labels=>\%labels,
                 -attributes=>\%attributes);

       popup_menu() creates a menu. Please note that the -multiple option will
       be ignored if passed - use scrolling_list() if you want to create a
       menu that supports multiple selections

       1.  The required first argument is the menu's name (-name).

       2.  The required second argument (-values) is an array reference
           containing the list of menu items in the menu.  You can pass the
           method an anonymous array, as shown in the example, or a reference
           to a named array, such as "\@foo".

       3.  The optional third parameter (-default) is the name of the default
           menu choice.  If not specified, the first item will be the default.
           The values of the previous choice will be maintained across
           queries. Pass an array reference to select multiple defaults.

       4.  The optional fourth parameter (-labels) is provided for people who
           want to use different values for the user-visible label inside the
           popup menu and the value returned to your script.  It's a pointer
           to an hash relating menu values to user-visible labels.  If you
           leave this parameter blank, the menu values will be displayed by
           default.  (You can also leave a label undefined if you want to).

       5.  The optional fifth parameter (-attributes) is provided to assign
           any of the common HTML attributes to an individual menu item. It's
           a pointer to a hash relating menu values to another hash with the
           attribute's name as the key and the attribute's value as the value.

       When the form is processed, the selected value of the popup menu can be
       retrieved using:

             $popup_menu_value = param('menu_name');

   Creating an option group
       Named parameter style

         print popup_menu(-name=>'menu_name',
                         -values=>[qw/eenie meenie minie/,
                                   optgroup(-name=>'optgroup_name',
                                                    -values => ['moe','catch'],
                                                    -attributes=>{'catch'=>{'class'=>'red'}})],
                         -labels=>{'eenie'=>'one',
                                   'meenie'=>'two',
                                   'minie'=>'three'},
                         -default=>'meenie');

         Old style
         print popup_menu('menu_name',
                         ['eenie','meenie','minie',
                          optgroup('optgroup_name', ['moe', 'catch'],
                                          {'catch'=>{'class'=>'red'}})],'meenie',
                         {'eenie'=>'one','meenie'=>'two','minie'=>'three'});

       optgroup() creates an option group within a popup menu.

       1.  The required first argument (-name) is the label attribute of the
           optgroup and is not inserted in the parameter list of the query.

       2.  The required second argument (-values)  is an array reference
           containing the list of menu items in the menu.  You can pass the
           method an anonymous array, as shown in the example, or a reference
           to a named array, such as \@foo.  If you pass a HASH reference, the
           keys will be used for the menu values, and the values will be used
           for the menu labels (see -labels below).

       3.  The optional third parameter (-labels) allows you to pass a
           reference to a hash containing user-visible labels for one or more
           of the menu items.  You can use this when you want the user to see
           one menu string, but have the browser return your program a
           different one.  If you don't specify this, the value string will be
           used instead ("eenie", "meenie" and "minie" in this example).  This
           is equivalent to using a hash reference for the -values parameter.

       4.  An optional fourth parameter (-labeled) can be set to a true value
           and indicates that the values should be used as the label attribute
           for each option element within the optgroup.

       5.  An optional fifth parameter (-novals) can be set to a true value
           and indicates to suppress the val attribute in each option element
           within the optgroup.

           See the discussion on optgroup at W3C
           (http://www.w3.org/TR/REC-html40/interact/forms.html#edef-OPTGROUP)
           for details.

       6.  An optional sixth parameter (-attributes) is provided to assign any
           of the common HTML attributes to an individual menu item. It's a
           pointer to a hash relating menu values to another hash with the
           attribute's name as the key and the attribute's value as the value.

   Creating a scrolling list
          print scrolling_list('list_name',
                                       ['eenie','meenie','minie','moe'],
               ['eenie','moe'],5,'true',{'moe'=>{'class'=>'red'}});
             -or-

          print scrolling_list('list_name',
                                       ['eenie','meenie','minie','moe'],
                                       ['eenie','moe'],5,'true',
               \%labels,%attributes);

               -or-

          print scrolling_list(-name=>'list_name',
                                       -values=>['eenie','meenie','minie','moe'],
                                       -default=>['eenie','moe'],
                                       -size=>5,
                                       -multiple=>'true',
               -labels=>\%labels,
               -attributes=>\%attributes);

       scrolling_list() creates a scrolling list.

       Parameters:

       1.  The first and second arguments are the list name (-name) and values
           (-values).  As in the popup menu, the second argument should be an
           array reference.

       2.  The optional third argument (-default) can be either a reference to
           a list containing the values to be selected by default, or can be a
           single value to select.  If this argument is missing or undefined,
           then nothing is selected when the list first appears.  In the named
           parameter version, you can use the synonym "-defaults" for this
           parameter.

       3.  The optional fourth argument is the size of the list (-size).

       4.  The optional fifth argument can be set to true to allow multiple
           simultaneous selections (-multiple).  Otherwise only one selection
           will be allowed at a time.

       5.  The optional sixth argument is a pointer to a hash containing long
           user-visible labels for the list items (-labels).  If not provided,
           the values will be displayed.

       6.  The optional sixth parameter (-attributes) is provided to assign
           any of the common HTML attributes to an individual menu item. It's
           a pointer to a hash relating menu values to another hash with the
           attribute's name as the key and the attribute's value as the value.

           When this form is processed, all selected list items will be
           returned as a list under the parameter name 'list_name'.  The
           values of the selected items can be retrieved with:

                 @selected = param('list_name');

   Creating a group of related checkboxes
          print checkbox_group(-name=>'group_name',
                                       -values=>['eenie','meenie','minie','moe'],
                                       -default=>['eenie','moe'],
                                       -linebreak=>'true',
                                       -disabled => ['moe'],
               -labels=>\%labels,
               -attributes=>\%attributes);

          print checkbox_group('group_name',
                                       ['eenie','meenie','minie','moe'],
               ['eenie','moe'],'true',\%labels,
               {'moe'=>{'class'=>'red'}});

          HTML3-COMPATIBLE BROWSERS ONLY:

          print checkbox_group(-name=>'group_name',
                                       -values=>['eenie','meenie','minie','moe'],
                                       -rows=2,-columns=>2);

       checkbox_group() creates a list of checkboxes that are related by the
       same name.

       Parameters:

       1.  The first and second arguments are the checkbox name and values,
           respectively (-name and -values).  As in the popup menu, the second
           argument should be an array reference.  These values are used for
           the user-readable labels printed next to the checkboxes as well as
           for the values passed to your script in the query string.

       2.  The optional third argument (-default) can be either a reference to
           a list containing the values to be checked by default, or can be a
           single value to checked.  If this argument is missing or undefined,
           then nothing is selected when the list first appears.

       3.  The optional fourth argument (-linebreak) can be set to true to
           place line breaks between the checkboxes so that they appear as a
           vertical list.  Otherwise, they will be strung together on a
           horizontal line.

       The optional -labels argument is a pointer to a hash relating the
       checkbox values to the user-visible labels that will be printed next to
       them.  If not provided, the values will be used as the default.

       The optional parameters -rows, and -columns cause checkbox_group() to
       return an HTML3 compatible table containing the checkbox group
       formatted with the specified number of rows and columns.  You can
       provide just the -columns parameter if you wish; checkbox_group will
       calculate the correct number of rows for you.

       The option -disabled takes an array of checkbox values and disables
       them by greying them out (this may not be supported by all browsers).

       The optional -attributes argument is provided to assign any of the
       common HTML attributes to an individual menu item. It's a pointer to a
       hash relating menu values to another hash with the attribute's name as
       the key and the attribute's value as the value.

       The optional -tabindex argument can be used to control the order in
       which radio buttons receive focus when the user presses the tab button.
       If passed a scalar numeric value, the first element in the group will
       receive this tab index and subsequent elements will be incremented by
       one.  If given a reference to an array of radio button values, then the
       indexes will be jiggered so that the order specified in the array will
       correspond to the tab order.  You can also pass a reference to a hash
       in which the hash keys are the radio button values and the values are
       the tab indexes of each button.  Examples:

         -tabindex => 100    #  this group starts at index 100 and counts up
         -tabindex => ['moe','minie','eenie','meenie']  # tab in this order
         -tabindex => {meenie=>100,moe=>101,minie=>102,eenie=>200} # tab in this order

       The optional -labelattributes argument will contain attributes attached
       to the <label> element that surrounds each button.

       When the form is processed, all checked boxes will be returned as a
       list under the parameter name 'group_name'.  The values of the "on"
       checkboxes can be retrieved with:

             @turned_on = param('group_name');

       The value returned by checkbox_group() is actually an array of button
       elements.  You can capture them and use them within tables, lists, or
       in other creative ways:

           @h = checkbox_group(-name=>'group_name',-values=>\@values);
           &use_in_creative_way(@h);

   Creating a standalone checkbox
           print checkbox(-name=>'checkbox_name',
                                  -checked=>1,
                                  -value=>'ON',
                                  -label=>'CLICK ME');

               -or-

           print checkbox('checkbox_name','checked','ON','CLICK ME');

       checkbox() is used to create an isolated checkbox that isn't logically
       related to any others.

       Parameters:

       1.  The first parameter is the required name for the checkbox (-name).
           It will also be used for the user-readable label printed next to
           the checkbox.

       2.  The optional second parameter (-checked) specifies that the
           checkbox is turned on by default.  Synonyms are -selected and -on.

       3.  The optional third parameter (-value) specifies the value of the
           checkbox when it is checked.  If not provided, the word "on" is
           assumed.

       4.  The optional fourth parameter (-label) is the user-readable label
           to be attached to the checkbox.  If not provided, the checkbox name
           is used.

       The value of the checkbox can be retrieved using:

           $turned_on = param('checkbox_name');

   Creating a radio button group
          print radio_group(-name=>'group_name',
                                    -values=>['eenie','meenie','minie'],
                                    -default=>'meenie',
                                    -linebreak=>'true',
                  -labels=>\%labels,
                  -attributes=>\%attributes);

               -or-

          print radio_group('group_name',['eenie','meenie','minie'],
                   'meenie','true',\%labels,\%attributes);


          HTML3-COMPATIBLE BROWSERS ONLY:

          print radio_group(-name=>'group_name',
                                    -values=>['eenie','meenie','minie','moe'],
                                    -rows=2,-columns=>2);

       radio_group() creates a set of logically-related radio buttons (turning
       one member of the group on turns the others off)

       Parameters:

       1.  The first argument is the name of the group and is required
           (-name).

       2.  The second argument (-values) is the list of values for the radio
           buttons.  The values and the labels that appear on the page are
           identical.  Pass an array reference in the second argument, either
           using an anonymous array, as shown, or by referencing a named array
           as in "\@foo".

       3.  The optional third parameter (-default) is the name of the default
           button to turn on. If not specified, the first item will be the
           default.  You can provide a nonexistent button name, such as "-" to
           start up with no buttons selected.

       4.  The optional fourth parameter (-linebreak) can be set to 'true' to
           put line breaks between the buttons, creating a vertical list.

       5.  The optional fifth parameter (-labels) is a pointer to an
           associative array relating the radio button values to user-visible
           labels to be used in the display.  If not provided, the values
           themselves are displayed.

       All modern browsers can take advantage of the optional parameters
       -rows, and -columns.  These parameters cause radio_group() to return an
       HTML3 compatible table containing the radio group formatted with the
       specified number of rows and columns.  You can provide just the
       -columns parameter if you wish; radio_group will calculate the correct
       number of rows for you.

       To include row and column headings in the returned table, you can use
       the -rowheaders and -colheaders parameters.  Both of these accept a
       pointer to an array of headings to use.  The headings are just
       decorative.  They don't reorganize the interpretation of the radio
       buttons -- they're still a single named unit.

       The optional -tabindex argument can be used to control the order in
       which radio buttons receive focus when the user presses the tab button.
       If passed a scalar numeric value, the first element in the group will
       receive this tab index and subsequent elements will be incremented by
       one.  If given a reference to an array of radio button values, then the
       indexes will be jiggered so that the order specified in the array will
       correspond to the tab order.  You can also pass a reference to a hash
       in which the hash keys are the radio button values and the values are
       the tab indexes of each button.  Examples:

         -tabindex => 100    #  this group starts at index 100 and counts up
         -tabindex => ['moe','minie','eenie','meenie']  # tab in this order
         -tabindex => {meenie=>100,moe=>101,minie=>102,eenie=>200} # tab in this order

       The optional -attributes argument is provided to assign any of the
       common HTML attributes to an individual menu item. It's a pointer to a
       hash relating menu values to another hash with the attribute's name as
       the key and the attribute's value as the value.

       The optional -labelattributes argument will contain attributes attached
       to the <label> element that surrounds each button.

       When the form is processed, the selected radio button can be retrieved
       using:

             $which_radio_button = param('group_name');

       The value returned by radio_group() is actually an array of button
       elements.  You can capture them and use them within tables, lists, or
       in other creative ways:

           @h = radio_group(-name=>'group_name',-values=>\@values);
           &use_in_creative_way(@h);

   Creating a submit button
          print submit(-name=>'button_name',
                               -value=>'value');

               -or-

          print submit('button_name','value');

       submit() will create the query submission button.  Every form should
       have one of these.

       Parameters:

       1.  The first argument (-name) is optional.  You can give the button a
           name if you have several submission buttons in your form and you
           want to distinguish between them.

       2.  The second argument (-value) is also optional.  This gives the
           button a value that will be passed to your script in the query
           string. The name will also be used as the user-visible label.

       3.  You can use -label as an alias for -value.  I always get confused
           about which of -name and -value changes the user-visible label on
           the button.

       You can figure out which button was pressed by using different values
       for each one:

            $which_one = param('button_name');

   Creating a reset button
          print reset

       reset() creates the "reset" button.  Note that it restores the form to
       its value from the last time the script was called, NOT necessarily to
       the defaults.

       Note that this conflicts with the perl reset() built-in.  Use
       CORE::reset() to get the original reset function.

   Creating a default button
          print defaults('button_label')

       defaults() creates a button that, when invoked, will cause the form to
       be completely reset to its defaults, wiping out all the changes the
       user ever made.

   Creating a hidden field
               print hidden(-name=>'hidden_name',
                                    -default=>['value1','value2'...]);

                       -or-

               print hidden('hidden_name','value1','value2'...);

       hidden() produces a text field that can't be seen by the user.  It is
       useful for passing state variable information from one invocation of
       the script to the next.

       Parameters:

       1.  The first argument is required and specifies the name of this field
           (-name).

       2.  The second argument is also required and specifies its value
           (-default).  In the named parameter style of calling, you can
           provide a single value here or a reference to a whole list

       Fetch the value of a hidden field this way:

            $hidden_value = param('hidden_name');

       Note, that just like all the other form elements, the value of a hidden
       field is "sticky".  If you want to replace a hidden field with some
       other values after the script has been called once you'll have to do it
       manually:

            param('hidden_name','new','values','here');

   Creating a clickable image button
            print image_button(-name=>'button_name',
                                       -src=>'/source/URL',
                                       -align=>'MIDDLE');

               -or-

            print image_button('button_name','/source/URL','MIDDLE');

       image_button() produces a clickable image.  When it's clicked on the
       position of the click is returned to your script as "button_name.x" and
       "button_name.y", where "button_name" is the name you've assigned to it.

       Parameters:

       1.  The first argument (-name) is required and specifies the name of
           this field.

       2.  The second argument (-src) is also required and specifies the URL

       3.  The third option (-align, optional) is an alignment type, and may
           be TOP, BOTTOM or MIDDLE

       Fetch the value of the button this way:
            $x = param('button_name.x');
            $y = param('button_name.y');

   Creating a javascript action button
            print button(-name=>'button_name',
                                 -value=>'user visible label',
                                 -onClick=>"do_something()");

               -or-

            print button('button_name',"user visible value","do_something()");

       button() produces an "<input>" tag with "type="button"".  When it's
       pressed the fragment of JavaScript code pointed to by the -onClick
       parameter will be executed.

WORKING WITH FRAMES
       It's possible for CGI.pm scripts to write into several browser panels
       and windows using the HTML 4 frame mechanism.  There are three
       techniques for defining new frames programmatically:

       1. Create a <Frameset> document
           After writing out the HTTP header, instead of creating a standard
           HTML document using the start_html() call, create a <frameset>
           document that defines the frames on the page.  Specify your
           script(s) (with appropriate parameters) as the SRC for each of the
           frames.

           There is no specific support for creating <frameset> sections in
           CGI.pm, but the HTML is very simple to write.

       2. Specify the destination for the document in the HTTP header
           You may provide a -target parameter to the header() method:

               print header(-target=>'ResultsWindow');

           This will tell the browser to load the output of your script into
           the frame named "ResultsWindow".  If a frame of that name doesn't
           already exist, the browser will pop up a new window and load your
           script's document into that.  There are a number of magic names
           that you can use for targets.  See the HTML "<frame>" documentation
           for details.

       3. Specify the destination for the document in the <form> tag
           You can specify the frame to load in the FORM tag itself.  With
           CGI.pm it looks like this:

               print start_form(-target=>'ResultsWindow');

           When your script is reinvoked by the form, its output will be
           loaded into the frame named "ResultsWindow".  If one doesn't
           already exist a new window will be created.

       The script "frameset.cgi" in the examples directory shows one way to
       create pages in which the fill-out form and the response live in side-
       by-side frames.

SUPPORT FOR JAVASCRIPT
       The usual way to use JavaScript is to define a set of functions in a
       <SCRIPT> block inside the HTML header and then to register event
       handlers in the various elements of the page. Events include such
       things as the mouse passing over a form element, a button being
       clicked, the contents of a text field changing, or a form being
       submitted. When an event occurs that involves an element that has
       registered an event handler, its associated JavaScript code gets
       called.

       The elements that can register event handlers include the <BODY> of an
       HTML document, hypertext links, all the various elements of a fill-out
       form, and the form itself. There are a large number of events, and each
       applies only to the elements for which it is relevant. Here is a
       partial list:

       onLoad
           The browser is loading the current document. Valid in:

                + The HTML <BODY> section only.

       onUnload
           The browser is closing the current page or frame. Valid for:

                + The HTML <BODY> section only.

       onSubmit
           The user has pressed the submit button of a form. This event
           happens just before the form is submitted, and your function can
           return a value of false in order to abort the submission.  Valid
           for:

                + Forms only.

       onClick
           The mouse has clicked on an item in a fill-out form. Valid for:

                + Buttons (including submit, reset, and image buttons)
                + Checkboxes
                + Radio buttons

       onChange
           The user has changed the contents of a field. Valid for:

                + Text fields
                + Text areas
                + Password fields
                + File fields
                + Popup Menus
                + Scrolling lists

       onFocus
           The user has selected a field to work with. Valid for:

                + Text fields
                + Text areas
                + Password fields
                + File fields
                + Popup Menus
                + Scrolling lists

       onBlur
           The user has deselected a field (gone to work somewhere else).
           Valid for:

                + Text fields
                + Text areas
                + Password fields
                + File fields
                + Popup Menus
                + Scrolling lists

       onSelect
           The user has changed the part of a text field that is selected.
           Valid for:

                + Text fields
                + Text areas
                + Password fields
                + File fields

       onMouseOver
           The mouse has moved over an element.

                + Text fields
                + Text areas
                + Password fields
                + File fields
                + Popup Menus
                + Scrolling lists

       onMouseOut
           The mouse has moved off an element.

                + Text fields
                + Text areas
                + Password fields
                + File fields
                + Popup Menus
                + Scrolling lists

       In order to register a JavaScript event handler with an HTML element,
       just use the event name as a parameter when you call the corresponding
       CGI method. For example, to have your validateAge() JavaScript code
       executed every time the textfield named "age" changes, generate the
       field like this:

        print textfield(-name=>'age',-onChange=>"validateAge(this)");

       This example assumes that you've already declared the validateAge()
       function by incorporating it into a <SCRIPT> block. The CGI.pm
       start_html() method provides a convenient way to create this section.

       Similarly, you can create a form that checks itself over for
       consistency and alerts the user if some essential value is missing by
       creating it this way:
         print start_form(-onSubmit=>"validateMe(this)");

       See the javascript.cgi script for a demonstration of how this all
       works.

LIMITED SUPPORT FOR CASCADING STYLE SHEETS
       CGI.pm has limited support for HTML3's cascading style sheets (css).
       To incorporate a stylesheet into your document, pass the start_html()
       method a -style parameter.  The value of this parameter may be a
       scalar, in which case it is treated as the source URL for the
       stylesheet, or it may be a hash reference.  In the latter case you
       should provide the hash with one or more of -src or -code.  -src points
       to a URL where an externally-defined stylesheet can be found.  -code
       points to a scalar value to be incorporated into a <style> section.
       Style definitions in -code override similarly-named ones in -src, hence
       the name "cascading."

       You may also specify the type of the stylesheet by adding the optional
       -type parameter to the hash pointed to by -style.  If not specified,
       the style defaults to 'text/css'.

       To refer to a style within the body of your document, add the -class
       parameter to any HTML element:

           print h1({-class=>'Fancy'},'Welcome to the Party');

       Or define styles on the fly with the -style parameter:

           print h1({-style=>'Color: red;'},'Welcome to Hell');

       You may also use the new span() element to apply a style to a section
       of text:

           print span({-style=>'Color: red;'},
                      h1('Welcome to Hell'),
                      "Where did that handbasket get to?"
                      );

       Note that you must import the ":html3" definitions to have the span()
       method available.  Here's a quick and dirty example of using CSS's.
       See the CSS specification at http://www.w3.org/Style/CSS/ for more
       information.

           use CGI qw/:standard :html3/;

           #here's a stylesheet incorporated directly into the page
           $newStyle=<<END;
           <!--
           P.Tip {
               margin-right: 50pt;
               margin-left: 50pt;
               color: red;
           }
           P.Alert {
               font-size: 30pt;
               font-family: sans-serif;
             color: red;
           }
           -->
           END
           print header();
           print start_html( -title=>'CGI with Style',
                             -style=>{-src=>'http://www.capricorn.com/style/st1.css',
                                      -code=>$newStyle}
                            );
           print h1('CGI with Style'),
                 p({-class=>'Tip'},
                   "Better read the cascading style sheet spec before playing with this!"),
                 span({-style=>'color: magenta'},
                      "Look Mom, no hands!",
                      p(),
                      "Whooo wee!"
                      );
           print end_html;

       Pass an array reference to -code or -src in order to incorporate
       multiple stylesheets into your document.

       Should you wish to incorporate a verbatim stylesheet that includes
       arbitrary formatting in the header, you may pass a -verbatim tag to the
       -style hash, as follows:

       print start_html (-style  =>  {-verbatim => '@import
       url("/server-common/css/'.$cssFile.'");',
                         -src    =>  '/server-common/css/core.css'});

       This will generate an HTML header that contains this:

        <link rel="stylesheet" type="text/css"  href="/server-common/css/core.css">
          <style type="text/css">
          @import url("/server-common/css/main.css");
          </style>

       Any additional arguments passed in the -style value will be
       incorporated into the <link> tag.  For example:

        start_html(-style=>{-src=>['/styles/print.css','/styles/layout.css'],
                                 -media => 'all'});

       This will give:

        <link rel="stylesheet" type="text/css" href="/styles/print.css" media="all"/>
        <link rel="stylesheet" type="text/css" href="/styles/layout.css" media="all"/>

       <p>

       To make more complicated <link> tags, use the Link() function and pass
       it to start_html() in the -head argument, as in:

         @h = (Link({-rel=>'stylesheet',-type=>'text/css',-src=>'/ss/ss.css',-media=>'all'}),
               Link({-rel=>'stylesheet',-type=>'text/css',-src=>'/ss/fred.css',-media=>'paper'}));
         print start_html({-head=>\@h})

       To create primary and  "alternate" stylesheet, use the -alternate
       option:

        start_html(-style=>{-src=>[
                                  {-src=>'/styles/print.css'},
                                  {-src=>'/styles/alt.css',-alternate=>1}
                                  ]
                           });

   Dumping out all the name/value pairs
       The Dump() method produces a string consisting of all the query's
       name/value pairs formatted nicely as a nested list. This is useful for
       debugging purposes:

           print Dump

       Produces something that looks like:

           <ul>
           <li>name1
               <ul>
               <li>value1
               <li>value2
               </ul>
           <li>name2
               <ul>
               <li>value1
               </ul>
           </ul>

       As a shortcut, you can interpolate the entire CGI object into a string
       and it will be replaced with the a nice HTML dump shown above:

           $q=CGI->new;
           print "<h2>Current Values</h2> $q\n";

BUGS
       Address bug reports and comments to:
       <https://github.com/leejo/CGI.pm/issues>

       See the <https://github.com/leejo/CGI.pm/blob/master/CONTRIBUTING.md>
       file for information on raising issues and contributing

       The original bug tracker can be found at:
       <https://rt.cpan.org/Public/Dist/Display.html?Queue=CGI.pm>

SEE ALSO
       CGI - The original source of this documentation / functionality

perl v5.38.0                      2023-10-09           CGI::HTML::Functions(3)