SOURCE

//  //call
//     function stdunt(n1, n2) {
//         console.log(this.name)        //this=>objs
//         console.log(this.name + n1 + n2)  //this=>8
//     }

//     let objs = {
//         name: 3
//     }

//     stdunt.call(objs, 2, 3)
//  //applay
//     function hello(name, age) {
//         console.log(this)
//         console.log(name);
//         console.log(name + this.name);
//         console.log(arguments)
//     }

//     let util = {
//         name: 234
//     }

//     hello.apply(util, ["tsrot", 24, 12, 45, 6]);

   //bind
    var person = {
        name: "tsrot",
        age: 24,
        sayHello: function (age) {
            console.log(this.name);
            console.log(age);
        }
    };
    var son = {
        name: "xieliqun"
    };
    var boundFunc = person.sayHello.bind(son);

    boundFunc(25)

    // call  可传值  apply  传数组  bind  返回新的函数