Commented Issue: AsyncFileUpload control - script not responding in FireFox when width property set [26687]

(originally reported by alansingfield)

If you have an AsyncFileUpload control within a <DIV> that constrains its width, and set the Width attribute of the control to wider than its container, the script never completes in Firefox.

<div style="width:100px">
<asp:AsyncFileUpload runat="server" Width="1000px"/>
</div>

The problem is caused by this part of the script:

_app_onload: function(sender, e) {
...
if (Sys.Browser.agent == Sys.Browser.Firefox) {
this._inputFile.size = 0;
var width = this._inputFile.offsetWidth;
this._inputFile.style.width = "";
while (this._inputFile.offsetWidth < width) {
this._inputFile.size++;

The final while() loop never terminates.

I suggest that a sanity check is put in there - if the offsetWidth does not change value after incrementing size, the loop should terminate.

Alan Singfield.
Comments: We're investigating it now...