1  //函数定义，参数为string，返回为string
2 Func<string, string> myFunc = delegate(string msg)
3 {
4       return "Msg:" + msg;
5 };

1  //Lambda
2  Func<string, string> myFuncSame = msg => "Msg:" + msg;

1  //函数调用
2  string message= myFuncSame("Hello world");

 1  public static Func<int, int> Func()
 2  {
 3      var myVar = 1;
 4      Func<int, int> inc = delegate(int var1)
 5      {
 6          //myVar能够记录上一次调用后的状态（值）
 7          myVar = myVar + 1;
 8          return var1 + myVar;
 9      };
10      return inc;
11  }

1 static void CsharpClosures()
2 {
3     var inc = Func();
4     Console.WriteLine(inc(5));//7
5     Console.WriteLine(inc(6));//9
6 }