it's a couple of hours that I'm stuck on what apparently seems a very silly problem and I cannot move forward.
Basically if I try to evaluate the following at any of the event handlers of an ASP.NET Web Form Page (ie at Page_Load):
ScriptManager.GetCurrent ( Page ).IsInAsyncPostBack
I always get the following error:
'System.Web.UI.IScriptManager' does not contain a definition for 'GetCurrent' and no extension method 'GetCurrent' accepting a first argument of type 'System.Web.UI.IScriptManager' could be found (are you missing a using directive or an assembly reference?)
However if I evaluate the same in any of the embedded UserControls' events I do get a boolean value returned.
Am I missing something very basic?
Are you using an AjaxControlToolkit-ScriptManager? I had also sometimes problems to debug the IsInAsyncPostBack value.
Change
ScriptManager.GetCurrent(Page).IsInAsyncPostBack
To
AjaxControlToolkit.ToolkitScriptManager.GetCurrent(Page).IsInAsyncPostBack