How to Detect Click of RadUpload Select button

Is there any way to detect the actual click event of the RadUpload Select button on the client side?  In other words when the user clicks Select to browse for a file, I want to immediately call a javascript function.  I understand that the control has to do a postback, but can call a javascript function before it does the postback?

Also, is there a way to detect, on the client side, that a file was actually selected?

Thanks

Hello Acadia,

I suggest you using the OnClientFileSelected event which the RadUpload control provides and set a javascript function for an event handler to implement your custom logic. Please, refer to this help article for more details about this client-side event and a sample code-snippet demonstrating its use.

Regarding the other question about detecting whether a file has actually been selected, you can check the value of the file input field via javascript - use the get_fileInputField to get the input field of the selected file which the eventArgs of the OnClientFileSelected provide. However, if you want to avoid someone type a path in the file input field instead of using the Browse dialog for selecting a file you can set the ReadOnlyFileInputs property of the RadUpload control to true.

Kind regards,
Sophy
the Telerik team