create a if statement to know what page you on in php?

[joe.attaboy]

There are a variety of elements in the global $_SERVER array that can provide file names, paths, etc. Also the system constant __FILE__ will provide the full local path and name of the current file.

You can use them to build an if statement that tells you precisely which file you're in.

http://www.php.net/manual/en/reserved.variables.server.php

 

[Santipheap K]

for example if you on page how.com/index.php then you go to how.com/index2.php

how to create a if statement to know you on page index.php???