If you form has asp:Fileupload control along with other controls like dropdownlist, calendar.. you will be facing standard problem of Fileupload control losing (the file) value when users click upload first and dropdown next. This problem can be solved by using Updatepanel.  (AJAX) Place all the controls inside updatepanel and place the FileUpload control and Upload button… (5 comments)

If you are using Update Panel and try to Export gridview contents to EXCEL or Word, your asp.net page will throw nasty error. “Sys.WebForms.PageRequestManagerParserErrorException” Its because AJAX & Response.write don’t go together.  By calling Response.Write() directly you are bypassing the normal rendering mechanism of ASP.NET controls. The bits you write are going straight out to the… (0 comment)