详解JS中Array对象扩展与String对象扩展的方法

/** * Created by laixiangran on 2016/01/07. * Array扩展 */ (function() { // 遍历数组 if (typeof Array.prototype.forEach != "function") { Array.prototype.forEach = function (fn, context) { for (var i = 0; i < this.length; i++) { if (typeof fn === "function" && Object.prototype.hasOwnProperty.call(this, i)) { fn.call(context, this[i], i, this); } } }; } // 让数组中的每一个元素调用给定的函数，然后把得到的结果放到新数组中返回 if (typeof Array.prototype.map != "function") { Array.prototype.map = function (fn, context) { var arr = []; if (typeof fn === "function") { for (var k = 0, length = this.length; k < length; k++) { arr.push(fn.call(context, this[k], k, this)); } } return arr; }; } // 把符合条件的元素放到一个新数组中返回 if (typeof Array.prototype.filter != "function") { Array.prototype.filter = function (fn, context) { var arr = []; if (typeof fn === "function") { for (var k = 0, length = this.length; k < length; k++) { fn.call(context, this[k], k, this) && arr.push(this[k]); } } return arr; }; } // 如果数组中的每个元素都能通过给定的函数的测试，则返回true，反之false if (typeof Array.prototype.every != "function") { Array.prototype.every = function (fn, context) { var passed = true; if (typeof fn === "function") { for (var k = 0, length = this.length; k < length; k++) { if (passed === false) break; passed = !!fn.call(context, this[k], k, this); } } return passed; }; } // 类似every函数，但只要有一个通过给定函数的测试就返回true if (typeof Array.prototype.some != "function") { Array.prototype.some = function (fn, context) { var passed = false; if (typeof fn === "function") { for (var k = 0, length = this.length; k < length; k++) { if (passed === true) break; passed = !!fn.call(context, this[k], k, this); } } return passed; }; } // 返回元素在数组的索引，没有则返回-1，从左到右 if (typeof Array.prototype.indexOf != "function") { Array.prototype.indexOf = function (item, index) { var n = this.length, i = index == null ? 0 : index < 0 ? Math.max(0, n + index) : index; for (; i < n; i++) { if (i in this && this[i] === item) { return i } } return -1 }; } // 返回元素在数组的索引，没有则返回-1，从右到左 if (typeof Array.prototype.lastIndexOf != "function") { Array.prototype.lastIndexOf = function (item, index) { var n = this.length, i = index == null ? n-1 : index < 0 ? Math.max(0, n + index) : index; for (; i >= 0; i--) { if (i in this && this[i] === item) { return i; } } return -1; }; } // 让数组元素依次调用给定函数，最后返回一个值（从左到右） if (typeof Array.prototype.reduce != "function") { Array.prototype.reduce = function (callback, initialValue) { var previous = initialValue, k = 0, length = this.length; if (typeof initialValue === "undefined") { previous = this[0]; k = 1; } if (typeof callback === "function") { for (k; k < length; k++) { this.hasOwnProperty(k) && (previous = callback(previous, this[k], k, this)); } } return previous; }; } // 让数组元素依次调用给定函数，最后返回一个值（从右到左） if (typeof Array.prototype.reduceRight != "function") { Array.prototype.reduceRight = function (callback, initialValue) { var length = this.length, k = length - 1, previous = initialValue; if (typeof initialValue === "undefined") { previous = this[length - 1]; k--; } if (typeof callback === "function") { for (k; k > -1; k-=1) { this.hasOwnProperty(k) && (previous = callback(previous, this[k], k, this)); } } return previous; }; } // 去掉重复项（唯一性），返回新数组 if (typeof Array.prototype.uniq != "function") { Array.prototype.uniq = function() { var arr = []; arr[0] = this[0]; for (var i = 1; i < this.length; i++) { if (arr.indexOf(this[i]) == -1) { arr.push(this[i]); } } return arr; }; } // 指定删除数组中某值 if (typeof Array.prototype.remove != "function") { Array.prototype.remove = function(item) { for (var i = this.length; i >= 0; i--) { if (item === this[i]) { this.splice(i, 1); } } return this; }; } // 打乱数组顺序 if (typeof Array.prototype.shuffle != "function") { Array.prototype.shuffle = function() { var i = this.length; while (i) { var j = Math.floor(Math.random()*i); var t = this[--i]; this[i] = this[j]; this[j] = t; } return this; }; } // 求数组的最大值 if (typeof Array.prototype.max != "function") { Array.prototype.max = function() { return Math.max.apply({}, this) }; } // 求数组的最小值 if (typeof Array.prototype.max != "function") { Array.prototype.min = function() { return Math.min.apply({}, this) }; } // 判断是否为数组 if (typeof Array.prototype.isArray != "function") { Array.prototype.isArray = function() { return Object.prototype.toString.apply(this) === "[object Array]"; }; } }());

/** * Created by laixiangran on 2015/12/12. * String扩展 */ (function() { // 十六进制颜色值的正则表达式 var reg = /^#([0-9a-fA-f]{3}|[0-9a-fA-f]{6})$/; // RGB颜色转换为16进制 if (typeof String.prototype.rgbToHex != "function") { String.prototype.rgbToHex = function() { var that = this; if (/^(rgb|RGB)/.test(that)) { var aColor = that.replace(/(?:\(|\)|rgb|RGB)*/g,"").split(","); var strHex = "#"; for (var i=0; i
        

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