C# IsAssignableFrom & IsInstanceOfType & IsSubclassOf & Is

直观测试代码如下:

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

public partial class NaviControl : UserControl, ITestControl {     public NaviControl()     {         InitializeComponent();         Load += NaviControl_Load;     }       private void NaviControl_Load(object sender, EventArgs e)     {         Debug.Print($"Base.IsAssignableFrom:");         Debug.Print($"{typeof(UserControl).IsAssignableFrom(this.GetType())}");//True         Debug.Print($"{typeof(ITestControl).IsAssignableFrom(this.GetType())}");//True         Debug.Print($"This.IsAssignableFrom:");         Debug.Print($"{this.GetType().IsAssignableFrom(typeof(UserControl))}");//False         Debug.Print($"{this.GetType().IsAssignableFrom(typeof(ITestControl))}");//False         Debug.Print($"Base.IsInstanceOfType:");         Debug.Print($"{typeof(UserControl).IsInstanceOfType(this)}");//True         Debug.Print($"{typeof(ITestControl).IsInstanceOfType(this)}");//True         Debug.Print($"This.IsSubclassOf:");         Debug.Print($"{this.GetType().IsSubclassOf(typeof(UserControl))}");//True         Debug.Print($"{this.GetType().IsSubclassOf(typeof(ITestControl))}");//False         Debug.Print($"This.Is:");         Debug.Print($"{(this is UserControl)}");//True         Debug.Print($"{(this is ITestControl)}");//True         } }