Hi Ivan,
We regret for the delayed response.
Since Numeric Textbox does not have AutoPostBack property, it is not possible to directly fire onTextChanged event when the user clicks on the up or down arrow on the NumericTextBox. So by using _doPostBack() in java script we should invoke the post back to the Numeric textbox and call the server side event. Please refer the below link to call server side events from client side:
http://www.west-wind.com/wconnect/weblog/ShowEntry.blog?id=481http://www.thescripts.com/forum/thread331809.htmlPlease try this and let me know if this helps.
Thanks,
Melba