Fires after the selected page has been changed.
The PageIndexChanged event's data class is EventArgs.
The PageIndexChanged event fires in the following cases:
- an end-user has switched between pages by clicking the Pager's numeric or navigation button;
- a new value has been assigned to the ASPxTreeList.PageIndex property in code.
End-users can switch the control to the ShowAllNodes mode by clicking the All item in the page size item dropdown window, or by clicking the All navigation button. In this case, the PageIndexChanged event fires and the ASPxTreeList.PageIndex property returns -1.