Trigger a function from other page when handler file (.ashx) is completed.

Hi guys, I wonder is it possible to trigger a function in .aspx file when handler file (.ashx) is completed?
Public Class MultipleUpload : Implements IHttpHandler, IRequiresSessionState Dim product As New DBproduct Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest context.Response.ContentType = "text/plain" context.Response.Expires = -1 Try 'trigger a function in webform1.aspx here Catch ex As Exception context.Response.Write("Error: " + ex.Message) End Try End Sub Public ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable Get Return False End Get End Property End Class