DBBaseContext :: doBeforeModify - Modify handler
The before modify handler is called, when a property or instance data has been modified (DBP_Modify event). Since modify events on the instance level are fired, whenever an attribute changes, it is usually not suggested to handle modify events in a type context. This can be handled in a better way in the TypeContext::doBeforeStore() handler.
When updating an instance directly without using property handle assignments, you should call the modify() function to signal the modify events.
The handler can be overloaded in specialized property and type context class implementations.
Return value: Execution error ( int32 )
The value is usually returned from context functions or actions in order to report the result of execution. The variable may contain following values:
- -1: function/action not executed
- 0: function executed normally
- 1-9: Function executed with errors. Error codes depend on the function/action called.