C#中这个算是什么

今天偶然看见个代码片段：

 delegate int Mydg(int a,int b); //声明一个委托
　　public static class LambdaTest 
　　{ 
　　  public static int add(int a, int b)
        {
            return a + b;
        }

        public static int minus(int a, int b)
        {
            return a - b;
        }

        public static int oper(this int a, int b, Mydg mydg)
        {
            return mydg(a,b);
        } 
          public static void Main()
        {
            Mydg md1 = new Mydg(add);
            Mydg md2 = new Mydg(minus);
            Console.WriteLine(1.oper(2,md1));
            Console.WriteLine(3.oper(1,md2));
            //下面使用lambda表达式
            Console.WriteLine(1.oper(2, (a, b) => a + b));
            Console.WriteLine(3.oper(1,(a,b)=>a-b));
        }
        
　　} 
　　

觉得和一个js片段类似，mark一下

require("sys");

function delegate(func, a, b) {
    return func(a, b);//天然的委托，或者说省略掉了委托，直接传递行为
}
var operation = {
    add:function (a, b) { return a + b; },
    minus:function (a, b) { return a - b; },
    divi:function (a, b) { return a / b; },
    mod:function (a, b) { return a % b; },
    multi:function (a, b) { return a * b; }
}
var arr = [];
arr[0] = delegate(operation.add, 1, 3);　　//直接定义 arr[0]=delegate(function(a,b){return a+b;},1,3);
arr[1] = delegate(operation.minus, 1, 3)　 //arr[1]　=delegate(function(a,b){return a-b;},1,3);
arr[2] = delegate(operation.divi, 1, 3)
arr[3] = delegate(operation.mod, 1, 3)
arr[4] = delegate(operation.multi, 1, 3)
for(var e in arr)
console.log(arr[e])