<com:TContent ID="Content">

<com:TTimeTriggeredCallback ID="Trigger" 
	ActiveControl.CausesValidation="false"
	OnCallback="Page.onTriggerCallback" Interval="2" />
Count: <com:TActiveLabel ID="count" Text="0" />
<com:TTextBox ID="testBox" />

<com:TRequiredFieldValidator
			        ControlToValidate="testBox"
			        Display="Dynamic"
			        ErrorMessage="Please insert a Text." />

<com:TCheckBox Text="Test2" Attributes.OnClick="console.log(this.checked)" AutoPostBack="True" />
</com:TContent>