Validation of property value in property calculator?

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This works, but one problem is that the validation of the property needs to be done before the object is created and from what I understand that is not possible to trigger using pc?

Property Calculator runs on the server so it cannot dynamically do validation on the metadata card before the object is checked in.

Like Joonas said, validation cannot happen in real time. But if you change event handler to be "BeforeCheckInChanges", validation should happen for new objects even if you do not check them in.

Awesome, this worked. 

Awesome, this worked.