Query_string

$ENV{"QUERY_STRING"}

[emon]

Help, I wish to use many link in my page with [IF] function, I can't because don't function 2 QUERY_STRING in my page!
Ex.
print "<a href=index.cgi>Home</a>
<br><a href=index.cgi?links>links</a>
<br><a href=index.cgi?about>About Us</a>";

$menu = $ENV{'QUERY_STRING'};
if ($menu eq "about") {&displayAbout;}
elsif ($menu eq "links") {&displayLinks;}
else {&displayHome;}

sub displayHome {
$h = $ENV{'QUERY_STRING'};
if ($h eq "de") {&de;}
elsif ($h eq "fr") {&fr;}
else {&en; print $home;}
print "<a href=$ENV{'SCRIPT_NAME'}>en</a>¦
<a href=$ENV{'SCRIPT_NAME'}?de>de</a>¦
<a href=$ENV{'SCRIPT_NAME'}?fr>fr</a>";
}

[rainborick]

The environment variable $ENV{'QUERY_STRING'} contains all of the HTTP request that comes after the "?". In order to extract the information from the query string, you need to parse it with something like: (untested code)

@pairs = split("\&",$ENV{'QUERY_STRING'});
 foreach $command (@pairs) {
 ($parameterName,$value) = split("=",$command);
 if ($parameterName eq 'menu') { $menu = $value; }
 }

You might also want to learn about using the CPAN module CGI.pm which simplifies common CGI interface issues. Good luck!

[emon]

Thanks rainborick!... but don't function!
Please, help me, write an example with: change lang and menu link in only one page.

[perl_diver]

hi emon,

The way you have your querystrings could work:

<a href=index.cgi?links>

you don't have to have a name/value pair, a single word can work. But your links would be better if they were written as name/value pairs:

<a href=index.cgi?name=value&name=value>

this way you can send multiple commands to your script and use the CGI module to process the commands, or send only one name/value pair it that's what you want to do. Say your links look like this:

<a href=index.cgi?com=about&lan=de>
<a href=index.cgi?com=links&lan=fr>

use strict; 
use CGI qw/:standard/; 
my $menu = param('com'); 
my $lan = param('lan'); 
if ($menu eq 'about') {&displayAbout;} 
elsif ($menu eq 'links') {&displayLinks;} 
else {&displayHome;} 
sub displayHome { 
 if ($lan eq 'de') {&de;} 
 elsif ($lan eq 'fr') {&fr;} 
 else {&en; print $home;} 
} 

Read the CGI documentation for more indepth explanations:

[perldoc.perl.org...]

[emon]

Thanks perl_diver, I have able to make this code! Is great!