control-name caption font-name foreground-colour background-colour border-type border-width left-follows top-follows right-follows bottom-follows pressed-func-name context

This property nominates the function to be called when a specific event occures for the control.

NOTE that when a control invokes a nominated function in response to an event, the XPE 'this' that is passed to the function belongs to module WINCTL

The invoked function may be an XPE function or method or an external C++ function or method.