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How to: Implement One-to-One Relationships

There are three types of relationships between objects. The type of a relationship that is created depends upon how related objects are defined. To learn about a particular relationship type, click a corresponding link below.

 

Let's consider a simple example of a One-to-One relationship, when both classes that participate in the relationship have properties with a reference to the instance of their opposite class. It's necessary to write extra code within the property's setter method for each class that participates in the relationship to ensure the relationship's integrity, i.e. when a new object is assigned to a reference property, the reference to the previous object instance should be cleared and the assigned object should reference the current one.

This technique can be implemented as shown in the following code example.

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