- CGI Application Example

This section provides a tutorial example of Perl CGI application: - Returning the result of any arithmetic expression like a calculator.

Here is a simple CGI application,

#- Copyright (c) All Rights Reserved.

   $res = "";
   $res = eval($exp) if ($exp);
   print "Content-Type: text/html\n\n";
   print "<html><body>\n";
   print "<b>Calculator:</b><br/>\n";
   print "<form action=\"/cgi-bin/\" method=\"GET\">\n";
   print "<table border=\"0\">\n";
   print "<tr><td align=\"right\">Expression:</td>\n";
   print "<td><input type=\"text\" name=\"exp\"";
   print   " value=\"$exp\"/></td></tr>\n";
   print "<tr><td align=\"right\">Result:</td>\n";
   print "<td>$res</td></tr>\n";
   print "<tr><td></td>\n";
   print "<td><input type=\"submit\" value=\"Evaluate\"/></td></tr>\n";
   print "</table></form>\n";
   print "</html></body>\n";
sub getValues {
   $query = $ENV{'QUERY_STRING'};
   @list = split( /\&/, $query);
   foreach (@list) {
      ($var, $val) = split(/=/);
      $val =~ s/\'//g;
      $val =~ s/\+/ /g;
      $val =~ s/%(\w\w)/sprintf("%c", hex($1))/ge;
      $exp = $val if ($var =~ /exp/);

Enjoy it.

Table of Contents

 About This Book

 Perl on Linux Systems

 ActivePerl on Windows Systems

 Data Types: Values and Variables

 Expressions, Operations and Simple Statements

 User Defined Subroutines

 Perl Built-in Debugger

 Name Spaces and Perl Module Files

 Symbolic (or Soft) References

 Hard References - Addresses of Memory Objects

 Objects (or References) and Classes (or Packages)

 Typeglob and Importing Identifiers from Other Packages

 String Built-in Functions and Performance

 File Handles and Data Input/Output

 Open Files in Binary Mode

 Open Directories and Read File Names

 File System Functions and Operations

 Image and Picture Processing

 Using DBM Database Files

 Using MySQL Database Server

 Socket Communication Over the Internet

 XML::Simple Module - XML Parser and Generator

 XML Communication Model

 SOAP::Lite - SOAP Server-Client Communication Module

 Perl Programs as IIS Server CGI Scripts

CGI (Common Gateway Interface)

 What Is Common Gateway Interface (CGI)?

 IIS Environment Variables

 QUERY_STRING - CGI Query String - CGI Application Example

 XML-RPC - Remote Procedure Call with XML and HTTP

 RPC::XML - Perl Implementation of XML-RPC

 Integrating Perl with Apache Web Server Module for Building Web Pages

 LWP::UserAgent and Web Site Testing

 Converting Perl Script to Executable Binary

 Managing Perl Engine and Modules on macOS

 Archived Tutorials


 Full Version in PDF/EPUB