Checking a field value before changing a status

Checking a field value before changing a status

Hi all,

I'm trying to create some code so my users cannot close a request unless they have the service value field populated.

So the "Status" field should check the "Total_Service_Value" field for a value other than blank, when I select either "Closed (Complete)" or "Closed (Failed)" status.

Is this possible ?  I've had a play but not sure of the code I need to put in.

Kind Regards

Matt