Telerik UI for ASP.NET Core Validator Basic Usage

Telerik UI for ASP.NET Core allows you to use client-side validation by utilizing the Kendo UI for jQuery Validator. The Validator is built around the HTML5 validation attributes, it supports a variety of built-in validation rules, and provides a convenient way for custom-rule handling. In any case that requires user input, activate the Validator on the form that contains the editors, which must be validated.

Also, you can use the Validator to handle the client-side validation when using DataAnnotation attributes. The Telerik UI HTML and Tag Helpers consume the DataAnnotation attributes that are added to the Model. The Validator automatically creates validation rules based on the unobtrusive HTML attributes.

This demo showcases a basic form with Telerik UI for ASP.NET Core editors, which is validated on the client using the Kendo UI for jQuery Validator. The Validator is activated when the page with the form is loaded, and, by default, the validation triggers when the respective input element loses focus. The validation attributes are specified for each editor through the HtmlAttributes() method.

Functionality and Features

• Using Validator with DataAnnotation аttributes—Enable the Validator to perform client-side validation based on the applied DataAnnotation attributes.
• Creating custom validation rules—Implement custom validation rules and custom messages.
• Using Validator with editable components—Extend the default validation rules of editable helpers, such as Grid and ListView.

This Validator example is part of unique collection of hundreds of ASP.NET Core demos, with which you can see all Telerik ASP.NET Core components and their features in action. View the source code of the demos from the library or directly adapt, and edit them and their theme appearance in Telerik REPL for ASP.NET Core or ThemeBuilder.