One reason could be that the browser wasn't able to load the client
validation JavaScript code. (WebUIValidation.js)
The following gets inserted into your web page when you use a validation
control. Notice the check for Page_ValidationVer.
If WebUIValidation.js didn't get loaded, Page_ValidationVer will be
undefined. Page_ValidationVer is the first definition in WebUIValidation.js
<script language="javascript" type="text/javascript">
<!--
var Page_ValidationActive = false;
if (typeof(clientInformation) != "undefined" &&
clientInformation.appName.indexOf("Explorer") != -1) {
if ((typeof(Page_ValidationVer) != "undefined") && (Page_ValidationVer
== "125"))
ValidatorOnLoad();
}
function ValidatorOnSubmit() {
if (Page_ValidationActive) {
return ValidatorCommonOnSubmit();
}
return true;
}
// -->
</script>
This next line should be in your web page as well. This again is inserted
once you use a validation control.
<script language="javascript" type="text/javascript"
src="/aspnet_client/system_web/1_1_4322/WebUIValidation.js"></script>
You can still validate on the server as well. Something we have to do here
since alot of our users are Mac based, if they're not running IE. (Safari or
Firefox).
if false = Page.IsValid Then
Validate()
End If
If true = Page.IsValid Then
' continue with your code
End If