Question

In VB6, textboxes have their CausesValidation property set to True by default. In this case, is there some autogenerated validation code as well when the Validate Event fires? I suppose that such autogenerated code would check, at a minimum, whether the field is non-empty.

Answer 1

To answer your question, no there is no autogenerated validation code associated with the TextBox Validation event. You’ll have to write your own where you can check the contents of a TextBox’s Text property, etc.

You might find the following useful:

The CausesValidation Property and the Validate Event – Visual Basic 6 TextBox Control

If you’re wondering how you might verify that a TextBox is ‘non-empty’ you might use the following validation event example from the link:

Private Sub txtRequired_Validate(Cancel As Boolean)
    ' Check that field is not empty.
    If txtRequired.Text = "" Then 
        MsgBox "Please enter something here", vbExclamation
        Cancel = True
    End If
End Sub