How to use progress bar in asp.net 2.0 using c#

Hi guys

            I am working in a project in which I have a task to upload files .So while i am uploading files I need to show the progressbar in the page_load function of webpage.I am developing my project using Visual studio2005 and C#.

        I don't have enough idea to complete this task.Please help me out guys as this is very urgent work.
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