You use UDI validators to help ensure that the correct information is entered into text fields on wizard pages in the UDI Wizard. UDI includes several built-in validators that help you perform typical validations of fields used for entering text, such as preventing users from entering invalid characters and ensuring that the field is not empty. When a validator detects an invalid entry in a text box, a message is displayed on the wizard page, and the Next button is disabled until all invalid entries are resolved.
UDI includes built-in validators that allow you to perform most of the validation necessary for deployment. For more information about the UDI built-in validators, see Built-in UDI Validators.
If your requirements go beyond the built-in UDI validators, you can write custom UDI validators. UDI validators are DLLs written in C++ that implement the IValidator interface. Register the DLL with the UDI Wizard Designer validator library by creating a UDI Wizard Designer configuration (.config) file and placing it in the installation_folder\Bin\Config folder (where installation_folder is the folder in which you installed MDT). For more information on developing custom UDI tasks, see the section, Creating Custom UDI Validators, in the MDT document User-Driven Installation Developers Guide.