How to customize Upload Control

I would like to use the file upload control.  But I would like  to customize

it so that only the pdf extension is available when browsing using that

control.   Is that possible, or is the user of that control stuck with the file

extentions that it shows at runtime (Like html, gif, jpeg etc).  Any sample code showing

how to modify the file extensions would be greatly appreciated.

 

Thanks in advance,

 feddev

 
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