Using a delegate in a subclass to override the virtual method in the superclass

When using a delegate method in SubClass, the method works as it should. The same if I cast SC to SubClass. However I wish that the delegate method in SubClass should override the method in SuperClass. Unfortunately, override is not a valid keyword when creating delegate methods and the delegate does not have any methods on it's own to designate it an override property. public class MainClass { public SuperClass SC; public MainClass() { SC = new SubClass(); SC.rotateCW(); // MessageBox with "CW/CCW called", correct! SC.rotateCCW(); // MessageBox with "CCW" <--- They should point to the same method!!! } public class SuperClass { public SuperClass() {} public virtual void rotateCW() {MessageBox.Show("CW");} public virtual void rotateCCW() {MessageBox.Show("CCW");} } // End superclass public class SubClass : SuperClass { public rotateCCWDelegate rotateCCW; public SubClass() { rotateCCW = new rotateCCWDelegate(this.rotateCW); } public override void rotateCW() { MessageBox.Show("CW/CCW called"); } public delegate void rotateCCWDelegate(); }

I'm not sure what you are tring to do but once a delegate is created, the method it is associated with never changes — delegate objects are immutable. maybe this is something like what you are trying to do: public delegate string MyDelegate(string msg); public class MainClass { public void ShowMessage(MyDelegate theDelegate) { MessageBox.Show(theDelegate("test")); } } public class SuperClass { public virtual string CreateMessage(string msg) { return "Base Class " + msg; } } // End superclass public class SubClass : SuperClass { public override string CreateMessage(string msg) { return "Derived Class " + msg ; } } private void button1_Click(object sender, System.EventArgs e) { MainClass mc = new MainClass(); SuperClass superc = new SuperClass(); mc.ShowMessage(new MyDelegate(superc.CreateMessage)); superc = new SubClass(); mc.ShowMessage(new MyDelegate(superc.CreateMessage)); }

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Administrator23y ago
I'm not sure what you are tring to do but once a delegate is created, the method it is associated with never changes — delegate objects are immutable. maybe this is something like what you are trying to do: public delegate string MyDelegate(string msg); public class MainClass { public void ShowMessage(MyDelegate theDelegate) { MessageBox.Show(theDelegate("test")); } } public class SuperClass { public virtual string CreateMessage(string msg) { return "Base Class " + msg; } } // End superclass public class SubClass : SuperClass { public override string CreateMessage(string msg) { return "Derived Class " + msg ; } } private void button1_Click(object sender, System.EventArgs e) { MainClass mc = new MainClass(); SuperClass superc = new SuperClass(); mc.ShowMessage(new MyDelegate(superc.CreateMessage)); superc = new SubClass(); mc.ShowMessage(new MyDelegate(superc.CreateMessage)); }