Hi friends document.getElementById(' ').value not working in popup

Ok well, Please make sure that you have your control txtSalesRep rendered in the ModalDialog. Check if the object is there and is of type input.

Let us say you have a button in the document, and that button should supplied with a id. Look at the below code: input id ='BtnTest' style ='z-index: 100; left: 8px; width: 102px; position: absolute;top:60px' type ='button' value ='button'/> The button element can be accessed using that id BtnTest. document.getElementById("BtnTest") will give you the instance of the button. Make sure the element you are accessing is given an id.