To get the selected file name on the server side without actually upload the file you have to do some work on the client...
1. FileUpload is represented as an <input> tag with
type
attribute set to
file...
2. On click do not post the page to the server but call a client-side JavaScript method to extract value attribute of the <input> tag - that's the file name
3. Send file name using some AJAX call to the server
See the jsFiddle sample of how to retrieve the selected file in JavaScript -
http://jsfiddle.net/Ltq5x6bb/[
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