addEventListener中this指向问题
addEventListener绑定事件的时候,事件回调函数里的this应该是指向产生事件的DOM元素,但是可以通过函数绑定修改this指向,特意写了个bind函数,但是不知道为什么不起作用?
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
hello
</body>
<script type="text/javascript">
(function(){
Function.prototype.bind = function() {
var fn = this, args = Array.prototype.slice.call(arguments), obj = args.shift();
return function() {
return fn.apply(obj, args.concat(Array.prototype.slice.call(arguments)));
};
};
function A() {}
A.prototype = {
addAnimations: function() {
// console.log("addAnimations");
},
animationsHandler: function(e){
this.out();
},
out: function(){
console.log(1);
},
init: function() {
console.log(this);
var handler = this.animationsHandler.bind(this);
document.body.addEventListener('click', this.animationsHandler, false);
this.addAnimations();
}
};
new A().init();
})();
</script>
</html>
小Queen
9 years, 10 months ago