Field Error Expression Property

Enter an expression in the Error Expression box to display an error message when a field is edited and the data entered fails validation. Normally, you enter either:

·       Literal: A text message enclosed in quotation marks.

·       Function: A call to a user-defined function that returns the message.

If you’re using a function, you can create your function from the Code page of the Visual FoxPro Project Manager.

The VPM Enterprise validation routine displays your error message in a system message window in the upper-right corner of an application’s main window. The VPM Enterprise validation routine displays the message if the data entered into the field fails the validation rules set up for the field on the field’s Edit - Integrity page in the Data Builder. If you don’t enter your own error message, VPM Enterprise displays “Invalid Input” when a field fails validation.

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Field Message Expression Property