You can extend a class by adding properties and relationships to its definition. Extending a class impacts all existing instances of that class – all instances of that class will be updated to include the new properties and relationships.

To extend a class

  1. If the Management Pack Explorer pane is not visible in the Authoring Tool, click View, and then click Management Pack Explorer.

  2. In the Management Pack Explorer pane, locate, and then right-click the class that you want to extend. Select Extend class.

  3. In the Target Management Pack dialog box, select an unsealed management pack to store the class extension and then click OK.

  4. The Class properties and relationship list on the Extension of <class> tab in the authoring pane displays the properties and the relationships of the class. Create new properties and relationships as follows:

    1. Click Create property and in the Create property dialog box, type an Internal name for the new property. Click Create.

    2. Click Create relationship and in the Create relationship dialog box, type an Internal name for the new relationship. Click Create.

    When extending a class, do not define a property with an ID that is already in use in that class.
  5. Locate and select the new property or relationship in the Class properties and relationship list, and modify its properties in the Details pane as needed.