There are clearly times when we'd like to ensure that the user has selected at least one checkbox from the checkbox list. (Check Box Lists present a list of grouped check boxes for the user to select one or more checkboxes from.) If you specify a Required Field Validator's property to the ID of a Check Box List Web control you will get an exception informing you that the Check Box List cannot be validated.Essentially, we only needed to override a couple of the methods from the class.Of course, our implementation is a bit weak - it's client-side support is nil and no code has been added to assist in displaying the Web control in toolbox in VS. Regardless, we have a useful, compiled control that took only a small handful of lines of code.If you set a validation control's , stating: "Control 'control ID' referenced by the Control To Validate property of 'validation Control ID' cannot be validated." There may be times, however, when you need to provide validation for a Check Box or Check Box List.Many Web pages with Terms of Service include a Check Box titled "I agree to the above terms" that must be checked before continuing.
Hi Rahul, I guess you want to show a Requierd Field Validator for ASP Check Box List.
But there is no field in the Check Box List to fill, so Requierd Field Validator doesn't work for this Control.
You can also download complete code example from below: Download C# Code Example Download Code Example VB.
Net Still does not resolve “Required Field Validator for Checkboxlist”?