i have just noticed something strange in some asp.net markup.
I have a standard form with a couple of textboxes and a submit button.
When clicked the code behind will attempt to perform some logic and then return.
If the input values are not valid it used to throw an exception.
The moment i wrapped the controls in an AJAX update panel and try to submit bad data, no exception is thrown and the panel returns like nothing was wrong.
Does anyone know how to return this to the previous behavior whilst keeping the update panel?
The expression it is thrown, but its handle by ajax, and now have be come Javascript errors, because now the full page is not loaded, but the error return back from javascript ajax call.
To see them just open your javascript error console :), how ever you do not need the expression as Raj say, you need to find other way to show your errors.
When I won to make some test and find my error, I remove the Ajax Panel for this reason, locate the error, fix them, then place back the Ajax Panel