<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Hello Bind!</title>
</head>
<body>
<div id="example"></div>
<script type="text/javascript">
this.x = 9;
var module = {
x: 81,
getX: function() { return this.x; }
};
module.getX(); // 81
var retrieveX = module.getX;
retrieveX(); // 9, because in this case, "this" refers to the global object
//这里相当于把getX的函数体赋给了一个全局对象，this自然就变了
// Create a new function with 'this' bound to module
//New programmers (like myself) might confuse the global var getX with module's property getX
//这里创建一个新的函数和retrieveX 一样也就是和getX一样，但是this指向module
var boundGetX = retrieveX.bind(module);
boundGetX(); // 81
</script>
</body>
</html>