Page.IsPostBack equivalent in PHP

Question

When working on the same page which accepts Post data, it is good to know whether there is a special function like the one in Asp.NET such as Page.IsPostBack. Maybe I could use isset($_POST) but I am thinking there could be a special function for that.

So I want to process the post data under that function give alerts during processing the post data, otherwise it is just a page request.

Answer 1

I am always using

if($_SERVER['REQUEST_METHOD'] == 'POST')