Directory Services

Determining the Classes Associated With an Object Instance

Every object in Active Directory has two attributes whose values identify the hierarchy of object classes of which the object is an instance.

Attribute Description
structuralObjectClass Identifies the structural and abstract classes of which the object is an instance. For example, the values for a user object can be:

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person

organizationalPerson

user

objectClass Identifies the classes included in structuralObjectClass, plus any auxiliary classes that are dynamically attached. For example, if a "vehicle" auxiliary class is attached to a user object, the values can be:

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vehicle

person

organizationalPerson

user

Be aware that neither of these attributes include auxiliary classes that are statically linked with the object classes of which the object is an instance. For example, the securityPrincipal auxiliary class is statically linked with the user class because it is included in the systemAuxiliaryClass values of the user classSchema object; it is not included in either the objectClass or stucturalObjectClass attributes of instances of the user class.