Required Field Validator - #is_required {}

Validate that the field contains a value.


   wf:wire(ButtonID, TextBoxID, #validate { validators=[
     #is_required { text="Required" }


  • text (string) - The text to display if validation fails.

  • unless_has_value (element id or list of element ids) - Don't fail this validation as long as the specified elements have values. This can be used for creating validators like "Please enter either a firstname or a company name."

See Also

*  [Validate Action](

*  [Validation Demos](

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