Setting Up Validation Expressions Visually

The Input Validator control uses validation expressions and the criteria specified in derived classes to set up validation for compatible input components. By using the Validation Configuration dialog, developers can quickly set up the characteristics of each input component's associated validation expression.

Setting Up Validation Expressions

Choosing Set Up Validation in the ValidationProvider component's context menu or clicking the corresponding link in the Property window will display the "Validation Configuration" dialog box. From this dialog, designers can select the input component that they wish to configure from a dropdown list and choose values, comparison operators, data types, and other options. Designers must click the Apply button to keep any changes.

Alternatively, when a compatible input component is selected in the Forms designer, the Validation Configuration dialog can be accessed through the input component's ValidationExpression property in the Property window of the Visual Studio designer. The ValidationExpression property is available both at design time and programmatically.

It is strongly recommended that only one ValidationProvider component be added to a Windows Form. Although a form with more than one ValidationProvider will compile, conflicts can arise between the validation expressions of the different validation providers used to configure the same input component.