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OBJ_ISA

Syntax | Return Value | Arguments | Keywords | Version History

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.

Syntax

Result = OBJ_ISA(ObjectInstance, ClassName)

Return Value

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.

Arguments

ObjectInstance

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.

ClassName

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

Keywords

None.

Version History

5.0
Introduced

  IDL Online Help (March 06, 2007)