2019/12/30 11:23

var foo = [] ;
foo[100] = 100 ;
//console.log(foo)   => [empty*100,100] foo.length = 101

for(var i in foo){
	//前一百个都是空值
	console.log("A" + i)
	//=>A100
}

来源：CSDN

作者：Sword_meaning

链接：https://blog.csdn.net/Sword_meaning/article/details/103763449