实例
<script>
//call和apply，都是可以改变this的指向
/*var obj1 = {
width: 30,
height: 50,
getArear: function() {
console.log(this.width*this.height);
},
getCube: function(w,h,l){
console.log(this.name+ "体积为"+ w*h*l);
}
}
obj1.getArear();
var obj2 = {
width: 20,
height: 40,
name:"obj2"
}
var obj3 = {
width:20,
height:40,
name:"obj3"
}
/!*obj2.__proto__ = obj1;
obj2.getArear();*!/
console.log(obj2);
obj1.getArear.call(obj2);//使用obj2替换了obj1中的getArear中的this
obj1.getCube(3,4,5);
obj1.getCube.call(obj2,2,3,4);//如果有参数的话则直接将参数写在后面的参数列表
obj1.getCube.apply(obj3, [2,5,8]);//apply方法和call方法唯一区别在于参数的写法，apply必须将参数写成数组的写法
//bind()方法，将生成一个新的函数，该函数也可以改变其中this指向，必须执行才可以
obj1.getCube.bind(obj3, 2,5,10)();//参数是按照Call的写法
var f = obj1.getCube.bind(obj2, 4,5,8);
f();*/
//------实例
function Body(weight){
this.weight = weight;
}
function Head(hairColor){
this.hairColor = hairColor;
this.changeHairColor = function(color){
this.hairColor = color;
}
}
function Arms(armsLen){
this.armsLen = armsLen;
}
function Person(obj){
this.name = obj.name;
Body.call(this, obj.weight);
Head.call(this, obj.hairColor);
Arms.call(this, obj.armsLen);
this.eat = function(){
console.log(this.name + " is eating")
this.weight++;
console.log(this.weight);
}
}
var p1 = new Person({
name:"张三",
weight:100,
hairColor:"red",
armsLen:60
})
console.log(p1);
p1.eat();
p1.changeHairColor("black");
console.log(p1);
</script>
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