this

https://segmentfault.com/q/1010000008856410

 

var num=1;
var myObject ={
num :2,
add:function(){
this.num=3;
(function(){
console.log(this);
this.num=4;
})();
console.log(this);
},
sub:function(){
console.log(this.num);
}
}

myObject.add();

console.log(myObject.num);
console.log(num);
var sub = myObject.sub;
sub();

自運行函數實際上是window對象調用它

https://segmentfault.com/q/1010000004648772

window.number = 1;
var obj = {
	number: 4,
	dbl : (function() {
		this.number *= 2;
		return function() {
			this.number *= 2;
		}
	})()
};

var dbl =obj.dbl;

dbl();

obj.dbl();
console.log(window.number);
console.log(obj.number);