C#

class T{delegate void D();static void Main(){new D(Main)();}}

class Example {
	delegate void StatusOutput(string text);

	static void Main() {
		DoSomeWork(new StatusOutput(System.Console.WriteLine));
		DoSomeWork(new StatusOutput(Alert));
	}

	static void Alert(string text) {
		System.Windows.Forms.MessageBox.Show(text, "Status Update");
	}

	static void DoSomeWork(StatusOutput output) {
		output("Working...");
		System.Threading.Thread.Sleep(2000);
		output("Done");
	}
}

void Test()
{
  string str="UnModified";
  RefTest(ref str);
  //str now == "Modified!"
}

void RefTest(ref string s)
{
   s="Modified!";
}

   char A = (char)65;
   int i = 66;
   char B = (char)i;