Figure out if you are showing all records in a DevExpress ASPxGridView with the "All" button, breaking out of pagination.

Wire up an event like this:

Whatever.PageIndexChanged += Whatever_PageIndexChanged;

 
 

Catch a variable like so:

private void Whatever_PageIndexChanged(object sender, EventArgs e)
{
   int pageIndex = (sender as ASPxGridView).PageIndex;

 
 

The number will reveal which page you are viewing. A value of zero means page one, a value of one means page two, a value of two means page three, and so on. A negative one means you've broken out of the pagination.