Vb net validating event
the property Client Validation Function sets the name of function or script that will do the validation. The first argument source identifies the source control to validate. The custom validators does not checks for whether there is some input in the control to be validated so you must need to attach a Required Field Validator in addition to a Custom Validator control, if you require that certain data should be present in the validated field.
You have to look at the Kofax Capture Developers Guide of the installed Kofax Capture version, to see what versions of Visual Studio are supported.
Here we are discussing an example in which we are implementing custom validation control Event.