When one object class is subclassed (inherits) from another class, there is an "Is A" relationship between them. The OBJ_ISA function is used to determine if an object instance is subclassed from the specified class. OBJ_ISA returns True (1) if the specified variable is an object and has the specified class in its inheritance graph, or False (0) otherwise.

Calling Sequence

Result = OBJ_ISA( ObjectInstance , ClassName )



A scalar or array variable for which the OBJ_ISA test should be performed. The result is of type byte, and has the same size and organization as ObjectInstance .


A string giving the name of the class for which ObjectInstance is being tested.