CGI.pm - a Perl5 CGI Library

Version 3.05, 04/12/2004, L. Stein

Abstract

This perl 5 library uses objects to create Web fill-out forms on the fly and to parse their contents. It provides a simple interface for parsing and interpreting query strings passed to CGI scripts. However, it also offers a rich set of functions for creating fill-out forms. Instead of remembering the syntax for HTML form elements, you just make a series of perl function calls. An important fringe benefit of this is that the value of the previous query is used to initialize the form, so that the state of the form is preserved from invocation to invocation.

Everything is done through a ``CGI'' object. When you create one of these objects it examines the environment for a query string, parses it, and stores the results. You can then ask the CGI object to return or modify the query values. CGI objects handle POST and GET methods correctly, and correctly distinguish between scripts called from <ISINDEX> documents and form-based documents. In fact you can debug your script from the command line without worrying about setting up environment variables.

A script to create a fill-out form that remembers its state each time it's invoked is very easy to write with CGI.pm:

#!/usr/local/bin/perl

use CGI qw(:standard);

print header;
print start_html('A Simple Example'),
    h1('A Simple Example'),
    start_form,
    "What's your name? ",textfield('name'),
    p,
    "What's the combination?",
    p,
    checkbox_group(-name=>'words',
		   -values=>['eenie','meenie','minie','moe'],
		   -defaults=>['eenie','minie']),
    p,
    "What's your favorite color? ",
    popup_menu(-name=>'color',
	       -values=>['red','green','blue','chartreuse']),
    p,
    submit,
    end_form,
    hr;

if (param()) {
    print 
	"Your name is",em(param('name')),
	p,
	"The keywords are: ",em(join(", ",param('words'))),
	p,
	"Your favorite color is ",em(param('color')),
	hr;
}
print end_html;

Select this link to try the script
More scripting examples
Source code examples from The Official Guide to CGI.pm

Downloading

Installation

Function-Oriented vs Object-Oriented Use

Creating a new CGI query object

Saving the state of the form

CGI Functions that Take Multiple Arguments

Creating the HTTP header

HTML shortcuts

Creating forms

Importing CGI methods

Retrieving CGI.pm errors