Hello,
i got a problem with $_GET[]. please see the below code and help me.

<?php
if(isset($_GET['_rp'])==1)
{
echo '1';
}
else if(isset($_GET['_rp'])==1)
{
echo '2';
}
?>

when i'm changing the value of _rp=2 it was showing the result as '1' but not '2'. Why this was happening please help me to solve..

The isset() function returns TRUE or FALSE. You probably wanted it this way:

if(isset($_GET['_rp']) && $_GET['_rp'] == 1)
...
elseif(isset($_GET['_rp']) && $_GET['_rp'] == 2)
...

thank you bro.
its working fine you rock :)