I have different kinds of Ajax validators(http://blogs.msdn.com/mattgi/archive/2007/01/23/asp-net-ajax-validators.aspx) in the UpdatePanel which validate different TextBoxs which have TextChanged event, and got the following two strange behavious.  I have tried the ASP.NET validators too and got the same problems.  I think the problem is from the Async postback of UpdatePanel.

1. Type in some invalid values in TextBox.  Once the focus leaves the TextBox, the validation error message appears for a second and then disappear. 

   - Expect result: The error message shoud not appear before the button is clicked.

2. Click a Button outside of UpdatePanel, the error messages can appear normally.  But once click any control that cause the post back, ALL error messages of other validators disappear.

  - Expect result: The error message for other validators should stay

 Can anyone explain why and find the solutions?  Thanks a lot!

Hello

To make the validators compatible with update panel set the EnableClientScript property to false . During asynchronous postback server side validation will work but since content is inside updatepanel the feedback will be immediate .

Are ther any way to do client validation first?  How to have other error messages stay on the page?