javascript中forin的问题

Question

js代码
var test = ["a","b","c"];
var a = [];
for(var i in test) {
a.push(i);
}
console.log(a);
a怎么为["0","1","2","remove","isTrue"]

Answer 1

没问题，firefox打印出来是1，2,3，最好还是不要for in，因为有些浏览器会添加自定义属性，也会一起遍历了