AJAX Control Toolkit -

This control is built on top of the ASP.NET AJAX Control Toolkit and is designed to extend the ASP.NET RequiredFieldValidator control.

It extends the RequiredFieldValidator control by setting the CSS for a required control if it is invalid. It also extends a label control associated with the required control.

For instance, if you have a form where you have a textbox that is required and that textbox has a ASP.NET RequiredFieldValidator control applied to it, you can use this control to set the textbox's CSS property should the RequiredFieldValidator indicate the textbox is empty. When the form is submitted, if the textbox is empty, your CSS class will be applied to the textbox client-side. You can also specify that a label control have your custom CSS class applied to it as well.

Tags

ajax aspdotnet control extenders requiredfieldvalidat toolkit validation