How to check whether UpdatePanel is posting back?

You can check whether the postback was asynchronous and whether it was issued by an update panel looking at these properties:

ScriptManager.GetCurrent(Page).IsInAsyncPostbackScriptManager.GetCurrent(Page).AsyncPostbackSourceElementID

I don't know if this will work any better than your solution, but have you tried?:

if (ScriptManager.GetCurrent(Page).IsInAsyncPostBack){    Control ctrl = GetControlThatCausedPostBack(Page);    if (ctrl is UpdatePanel)    {        //handle updatepanel postback    }}private Control GetControlThatCausedPostBack(Page page){    //initialize a control and set it to null    Control ctrl = null;    //get the event target name and find the control    string ctrlName = Page.Request.Params.Get("__EVENTTARGET");    if (!String.IsNullOrEmpty(ctrlName))        ctrl = page.FindControl(ctrlName);    //return the control to the calling method    return ctrl;}

Try out following:

var controlName = Page.Request.Params.Get("__EVENTTARGET");if (!String.IsNullOrEmpty(controlName)){     // Use FindControl(controlName) to see whether      // control is of UpdatePanel type}

Helpful links:

• ASP.NET: Recursive FindControl & Extension Methods