How to enable/disable textbox if the user already pick a file for upload using AsyncFileUpload?

Question

I have an ASP code:

<ajax:AsyncFileUpload ID="fuFile" runat="server" Width="250px" />

with a textbox for description:

<asp:TextBox ID="txtFileDesc" runat="server" TextMode="MultiLine" Wrap="true" style=" resize: none" Height="50px" MaxLength="200"></asp:TextBox>

Now, I want to enable the txtFileDesc textbox if the user "PICKED A FILE" (when the background of the file path turns green) like this sample from http://www.asp.net .

I already tried the solution from other post's but none of them works for me.

Answer 1

you can handle OnClientUploadStarted client side event to disable textbox and OnClientUploadComplete event to enable textbox after file has been uploaded completely.

Your fileupload should be like

<ajax:AsyncFileUpload ID="fuFile" runat="server" Width="250px" OnClientUploadStarted="OnClientUploadStartedFn" OnClientUploadComplete="OnClientUploadCompleteFn"  />

call this function on OnClientUploadStarted

 function OnClientUploadStartedFn () {
    $('#textboxId').attr('readonly','readonly');
   }

call this function on OnClientUploadComplete

function OnClientUploadCompleteFn() {
    $('#textboxId').removeAttr('readonly');
   }