IsSubclassOf & IsAssignableFrom

IsSubclassOf

• 类继承测试

public class ClassA { }
public class ClassB : ClassA { }
public class ClassC : ClassB { }

Console.WriteLine(typeof(ClassB).IsSubclassOf(typeof(ClassA))); // TRUE
Console.WriteLine(typeof(ClassB).IsSubclassOf(typeof(ClassB))); // FALSE
Console.WriteLine(typeof(ClassB).IsSubclassOf(typeof(ClassC))); // FALSE
Console.WriteLine(typeof(ClassC).IsSubclassOf(typeof(ClassA))); // TRUE
Console.WriteLine(typeof(ClassC).IsSubclassOf(typeof(ClassB))); // TRUE

IsSubclassOf用于判断class之间是否继承。接口之间的继承无法进行判断。

• 接口继承测试

public interface ID { }
public interface IE : ID { }
public class ClassD : ID { }
Console.WriteLine(typeof(ClassD).IsSubclassOf(typeof(ID))); // FALSE
Console.WriteLine(typeof(IE).IsSubclassOf(typeof(ID));      // FALSE

• 泛型类测试

public class ClassF { }
public class ClassG : ClassF { }
public class ClassH : ClassF { }
// no type constraint, no good
Console.WriteLine(typeof(ClassG<>).IsSubclassOf(typeof(ClassF<>))); //FALSE
// no covariance support here
Console.WriteLine(typeof(string).IsSubclassOf(typeof(object))); // TRUE
 Console.WriteLine(typeof(ClassG).IsSubclassOf(typeof(ClassF