Gets a hash code for this DependencyObject. 네임스페이스: System.Windows
상속자 참고 사항: DependencyObject overrides and then seals two Object methods: Equals and GetHashCode. The overrides call the Object implementations, resulting in an object equality behavior. The purpose of these deliberate overrides is to prevent derived classes from trying to define a value equality for a DependencyObject. Value equalities for DependencyObject will never be accurate because of the innate property value-changing capabilities of a DependencyObject, such as data binding and the WPF property system.