函数map方法 - zymonody - 沸点 - 掘金

2年前

#每日一题# 函数map方法
Array.prototype.myMap = function (callback, thisArg) {
let length = this.length
let res = []
if (!Array.isArray(this)) throw new TypeError('this is not an array')
if (typeof callback !== 'function') throw new TypeError(callback + 'is not a function')
if (length === 0) {
return res
}
for (let i = 0; i < length; i++) {
res[i] = callback.call(thisArg, this[i], i, this)
}
return res
}

展开

技术交流圈