let obj = { // 已有對象
name: 'xss'
age: 23
};
// 開始
obj[Symbol.iterator] = function(){
let iterator = {next: next};
let current = this;
const keys = Object.keys(current);
let index = 0;
function next() {
if(index<keys.length) {
return {
value: keys[index++], // 注意，這裏返回的是key
done: false
}
} else {
return {
done: true
}
}
}
return iterator
}
// 使用for...of... 遍歷
for(let k of obj) {
console.log(k+':'+obj[k])
}