If you have a method in a struct that modifies a data member of the struct, you can run into unexpected results, due to the value type semantics of the struct.
Assume that we have a struct that includes a method that can change the value of one of its data members. The method works just fine for a locally defined instance of the struct.
1 2 3 4 5 | // Method that modifies struct works if localDogCollarInfo collar = new DogCollarInfo(0.5, 8.0);<span class="skimlinks-unlinked">collar.Dump</span>();collar.DoubleLength();<span class="skimlinks-unlinked">collar.Dump</span>(); |
But if you have a property of some class whose type is this struct, it’s no longer safe to call this method. Because the property’s get accessor returns a copy of the struct, the data in the original struct won’t get modified.
1 2 3 4 5 6 | // Does not work if struct is propertyDog d = new Dog("Kirby");d.Collar = new DogCollarInfo(0.5, 8.0);<span class="skimlinks-unlinked">d.Collar.Dump</span>();d.Collar.DoubleLength();<span class="skimlinks-unlinked">d.Collar.Dump</span>(); // Length not doubled! |
