说明
ES6 从入门到精通系列（全23讲）学习笔记。
遍历器
entries()，keys()，values()， 返回一个遍历器，可以使用 for···of 循环进行遍历
keys()：对值遍历values()：对键值对遍历entries()：对键名遍历
console.log(["k", "a", "i", "m", "o"].keys()); console.log(["k", "a", "i", "m", "o"].values()); console.log(["k", "a", "i", "m", "o"].entries());
for (let key of ["k", "a", "i", "m", "o"].keys()) { console.log(key); } for (let value of ["k", "a", "i", "m", "o"].values()) { console.log(value); } for (let [key, value] of ["k", "a", "i", "m", "o"].entries()) { console.log(key, value); }
includes
includes() 返回一个布尔值，表示某个数组是否包含给定的值
console.log([1,2,3].indexOf(1) > -1) console.log([1,2,3].includes(1))
