PowerBuilder · Exception
What does NullObjectError System Exception mean in PowerBuilder?
This RuntimeError descendant is thrown whenever a script references a method, property, or event on an object reference that was never instantiated or has already been destroyed. It commonly surfaces when a control reference is used before Open()/CREATE runs, or after DESTROY has already released the object.
This RuntimeError descendant is thrown whenever a script references a method, property, or event on an object reference that was never instantiated or has already been destroyed. It commonly surfaces when a control reference is used before Open()/CREATE runs, or after DESTROY has already released the object.
Catch NullObjectError around the suspect call and check the reference with IsValid() or an explicit null test before invoking members on it. Trace GetMessage() and the object/routine name back to the exact statement that dereferenced the null instance.