jQuery('[attribute$="value"]') - Doesn't work

jQuery('[attribute$="value"]') - Doesn't work

Hi!
I'm doing something like this:

$('#Buttons li a').click(function(){
...
var ext=0;
if($('this[href$=".html"]'))
{
ext=5;
}
else if($('this[href$=".php"]'))
{
ext=4;
}
window.location.hash = $(this).attr('href').substr(0,$(this).attr('href').length-ext);






...


The problem is that I'm clicking in a <a> with the href="test.php" but it never enters in the "else if" and I don't know why...
Thanks for your time.