call、apply/bind的区别和用法(简单粗暴的解释)

var obj1={
 name:"bob",
 age:20    
}

var obj2={
 name:"coco",
 age:22
}

function getAge(){
 console.log(this.age)
}

var age = 50;

getAge(); //50 等价window.getAge();

getAge.call(obj1) //20 //相当于callback
getAge.apply(obj2)//22 //让函数服务于不同的对象;

call和apply的区别

var str = {
  name:"wow",
  age:"18",
  search:function(sex,addr){
    console.log(this.name+ "和性别" + sex + "和地址" + addr )
  }
}

var str1 = {
  name:20
}

var str2 = {
  name:23
}

str.search.call(str1,"男","江西")     //20和性别男和地址江西
str.search.apply(str2,["女","湖北"])  //23和性别女和地址湖北
总结:区别就是apply传参是数组;

call继承函数对象的属性:
function Person(){
 this.name = "bow",
 this.like = "吃东西"
}

function Son(){
 Person.call(this); //等价于Person();
 this.stre = "你好"
}
var aa = new Person();
console.log(aa);
var bb = new Son();
console.log(bb)
bind使用
var name = "name -g" var obj = { name:"bob" getName:function(){ console.log(this.name); //动态绑定,运行时,是谁做的。 } } obj.getName();//输出bob var fn = obj.getName; fn(); //等价于window.fn();输出"name -g"; var fn1 = obj.getName.bind(obj); fn1();//输出bob;

 

posted @ 2017-12-10 21:10  鱼樱前端  阅读(417)  评论(0编辑  收藏  举报