Client-side set allowed file extensions

[Scott]

I was hoping to set the allowed file extensions based on some chosen radio buttons, but the sample code in the on-line documentation does not work. I am weak in my javascript, so I am probably missing something simple. Here's the documentation page:
http://www.telerik.com/help/aspnet-ajax/asyncupload-client-object.html

and here's the sample code it provides:

function AllowJPEGExtension() {
  var upload = $find("<%= RadAsyncUpload1.ClientID %>");

  if (!upload.isExtensionValid(".jpeg"))
  {
     var exts = upload.get_allowedFileExtensions();
     exts[exts.length] = ".jpeg";
  }
}

[Princy]

Hi,

I guess you need to allow file extensions based on the radio button selection. Here is the code I tried from server side which worked as expected.

ASPX:

<asp:RadioButtonList ID="RadioButtonList1" runat="server" RepeatDirection="Horizontal"
    AutoPostBack="true" OnSelectedIndexChanged="RadioButtonList1_SelectedIndexChanged">
    <asp:ListItem Text="jpg"></asp:ListItem>
    <asp:ListItem Text="doc"></asp:ListItem>
    <asp:ListItem Text="pdf"></asp:ListItem>
</asp:RadioButtonList>
<br />
<telerik:RadAsyncUpload ID="RadAsyncUpload1" runat="server">
</telerik:RadAsyncUpload>

C#:

protected void RadioButtonList1_SelectedIndexChanged(object sender, EventArgs e)
{
    string file = RadioButtonList1.SelectedItem.Text;
    RadAsyncUpload1.AllowedFileExtensions = new string[] {file};
}

Thanks,
Princy.

[Scott]

Thank you Princy for providing a server-side solution.  Does anyone have a client-side solution?

[Plamen]

Hello Scott,

 
RadAsyncUpload does not support such client change in the allowed extensions because it would cause a security by providing possibility to upload unwanted files. 

In your scenario since you only want to control this behavior with radio button instead of using the "AllowedFileExtensions" you can use OnClientFileUploading event and cancel the uploading file if its extension is not the desired one as in the code below:

function OnClientFileUploading(sender, args) {
               var fileExtention = args.get_fileName().substring(args.get_fileName().lastIndexOf('.') + 1, args.get_fileName().length);
               alert(fileExtention);
           }

Please have in mind that this can easily be overriden so if you strongly need this validation you will have to use server-side way described earlier.

Hope this will explain the issue.
All the best,
Plamen
the Telerik team

[Scott]

Thank you Plamen.  If possible, you may want to request a change to the documentation, since the sample code I mentioned is apparently wrong.

[Plamen]

Hi Scott,

 
I already did this. Thank you very much for your concern with Telerik controls.

All the best,
Plamen
the Telerik team