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<title>call方法</title>
<script type="text/javascript" src="jquery.js"></script>
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<body>
<script>
$(document).ready(function(){
})
$().ready(function(){
//do something
})
//参考：http://uule.iteye.com/blog/1158829
$(function(){
//------------1.常例--------------
function add(a,b)
{
alert(a+b);
}
function sub(a,b)
{
alert(a-b);
}
add.call(sub,3,1);//4
//---------------常例（1）--------------------
function add1(a,b)
{
//this(a,b);
alert(a+b);
}
function sub1(a,b)
{
this(a,b);
alert(a-b);
}
add1.call(sub1,3,1); //弹出4
//---------------常例（2）--------------------
function add2(a,b)
{
this(a,b);
alert(a+b);
}
function sub2(a,b)
{
// this(a,b);
alert(a-b);
}
add2.call(sub2,3,1); //依次弹出2和4，add2的this被替换指向sub2
//----------2.-------------------------
function Animal(){
this.name = "Animal";
this.showName = function(){
alert(this.name);
}
}
function Cat(){
this.name = "Cat";
}
var animal = new Animal();
var cat = new Cat();
//通过call或apply方法，将原本属于Animal对象的showName()方法交给对象cat来使用了。
animal.showName.call(cat,",fw45tg354,'"); //Cat,此处call方法的第二个参数字符串可为任意的输出结果认为Cat
//animal.showName.apply(cat,[]);//Cat
//----------------3.实现继承-----------------------------
function Animal1(name){
this.name = name;
this.showName = function(){
alert(this.name);
}
}
function Cat1(name){
Animal1.call(this, name);
}
// Cat1.prototype = new Animal1();
var cat1 = new Cat1("Black Cat");
cat1.showName();//Black Cat
alert("是此类型？："+cat1 instanceof Animal1); //false
//-----------4.多重继承----------------------------
function Class10()
{
this.showSub = function(a,b)
{
alert(a-b);
}
}
function Class11()
{
this.showAdd = function(a,b)
{
alert(a+b);
}
}
function Class2()
{
Class10.call(this);
Class11.call(this,6,2);
}
var c2 = new Class2();
c2.showSub(8,3);//5
c2.showAdd(6,2);//8
})
//---------5.使用call方法调用匿名函数---------------------
var animals = [
{species: 'Lion', name: 'King'},
{species: 'Whale', name: 'Fail'}
];
for (var i = 0; i < animals.length; i++) {
(function (i) {
this.print = function () {
console.log('#' + i + ' ' + this.species + ': ' + this.name);
}
this.print();
}).call(animals[i], i);
//#0 Lion: King
//#1 Whale: Fail
}
//---------6.使用call方法调用函数并且指定上下文的'this'-------------
//在下面的例子中，当调用 greet 方法的时候，该方法的 this 值会绑定到 i 对象。
function greet() {
var reply = [this.person, 'Is An Awesome', this.role].join(' ');
console.log(reply);
}
var i = {
person: 'Douglas Crockford', role: 'Javascript Developer'
};
greet.call(i); // Douglas Crockford Is An Awesome Javascript Developer
</script>
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