//实现call

			var that = this ; //小程序环境

			function mySymbol(obj){

				let unique = (Math.random() + new Date().getTime()).toString(32).slice(0,8);

				if(obj.hasOwnProperty(unique)){

					return mySymbol(obj)

				}else {

					return unique;

				}

			}

			let Person = {

				name:'Tom',

				say(age = 23,city = '宁波',job = '前端'){

					console.log(`我叫${this.name},今年${age},在${city},从事${job}`)

				}

			}

			let Person1 = {

				name:'Tom1'

			}

			Function.prototype.MyCall = function(context){

				context =context || that; //小程序环境 PC环境为context =context || window;

				let fn = mySymbol(context);

				context.fn = this;

				let arg = [...arguments].slice(1);

				context.fn(...arg);

				delete context.fn;

			}

			Person.say.MyCall(Person1,23,'宁波','前端');

			Person.say.call(Person1,23,'宁波','前端');

			//实现apply

			Function.prototype.myApply = function(cxt,args){

				    cxt = cxt||that; //小程序环境为cxt = cxt||that; PC环境为cxt = cxt||window;

				    var fn = mySymbol(cxt);

				    cxt[fn] = this;

				    var result = cxt[fn](...args);

				    return result;

			}

			Person.say.myApply(Person1,['23','宁波','前端'])

			Person.say.apply(Person1,['23','宁波','前端'])

			Function.prototype.myBind = function(context){

				let self = this;

				let arg = [...arguments].slice(1);

				return function(){

					let newArg = [...arguments];

					return self.apply(context,arg.concat(newArg))

				}

			}

			let fn = Person.say.myBind(Person1,23);

			fn();

			fn('宁波','前端')