Implementation of IsPostBack in page load

Question

The more I use ASP.NET, the more if (!IsPostBack) {} seems pointless...

First example:

For example, I just Googled an issue, they said use this

Answer 1

It's for processing form data.

If you want to handle POSTed data, you only want to do so if the page actually posted data, not on first load. Hence, the IsPostBack flag.