#646 – Value Types Don’t Have Finalizers

In .NET, you override the Object.Finalize method to dispose of any unmanaged resources when the object is being garbage collected.  In C#, you write this finalizer using the destructor (~) syntax.  You can also implement the Dispose pattern to allow users of your object to deterministically dispose of  resources.

You cannot implement a finalizer or the dispose pattern for a value type.  A finalizer makes no sense for a value type because value typed objects are not garbage collected–they simply die when they go out of scope.

Since the finalizer and the dispose pattern exist for the purpose of releasing unmanaged resources, and you can’t implement either for a value type, you should avoid using unmanaged resources in value types.  A user would have to explicitly call some method to do the cleanup and there is no guarantee that they would remember to call the method.