转自：http://www.cnblogs.com/kissdodog/p/3386480.html
<head> <title>测试JS扩展方法</title> <script type="text/javascript"> // 合并多个空白为一个空白 String.prototype.ResetBlank = function() { //对字符串扩展 var regEx = /s+/g; return this.replace(regEx, ' '); }; window.onload = function() { var str = "你 在他想还好吗?"; alert(str); str = str.ResetBlank(); //这样就能够调用了，跟C#的很像吧! alert(str); } </script> </head>
// 清除两边的空格 String.prototype.trim = function() { return this.replace(/(^s*)|(s*$)/g, ''); }; // 合并多个空白为一个空白 String.prototype.ResetBlank = function() { var regEx = /s+/g; return this.replace(regEx, ' '); }; // 保留数字 String.prototype.GetNum = function() { var regEx = /[^d]/g; return this.replace(regEx, ''); }; // 保留中文 String.prototype.GetCN = function() { var regEx = /[^u4e00-u9fa5uf900-ufa2d]/g; return this.replace(regEx, ''); }; // String转化为Number String.prototype.ToInt = function() { return isNaN(parseInt(this)) ? this.toString() : parseInt(this); }; // 得到字节长度 String.prototype.GetLen = function() { var regEx = /^[u4e00-u9fa5uf900-ufa2d]+$/; if (regEx.test(this)) { return this.length * 2; } else { var oMatches = this.match(/[x00-xff]/g); var oLength = this.length * 2 - oMatches.length; return oLength; } }; // 获取文件全名 String.prototype.GetFileName = function() { var regEx = /^.*/([^/?]*).*$/; return this.replace(regEx, '$1'); }; // 获取文件扩展名 String.prototype.GetExtensionName = function() { var regEx = /^.*/[^/]*(.[^.?]*).*$/; return this.replace(regEx, '$1'); }; //替换所有 String.prototype.replaceAll = function(reallyDo, replaceWith, ignoreCase) { if (!RegExp.prototype.isPrototypeOf(reallyDo)) { return this.replace(new RegExp(reallyDo, (ignoreCase ? "gi" : "g")), replaceWith); } else { return this.replace(reallyDo, replaceWith); } }; //格式化字符串 add By 刘景宁 2010-12-09 String.Format = function() { if (arguments.length == 0) { return ''; } if (arguments.length == 1) { return arguments[0]; } var reg = /{(d+)?}/g; var args = arguments; var result = arguments[0].replace(reg, function($0, $1) { return args[parseInt($1) + 1]; }); return result; }; // 数字补零 Number.prototype.LenWithZero = function(oCount) { var strText = this.toString(); while (strText.length < oCount) { strText = '0' + strText; } return strText; }; // Unicode还原 Number.prototype.ChrW = function() { return String.fromCharCode(this); }; // 数字数组由小到大排序 Array.prototype.Min2Max = function() { var oValue; for (var i = 0; i < this.length; i++) { for (var j = 0; j <= i; j++) { if (this[i] < this[j]) { oValue = this[i]; this[i] = this[j]; this[j] = oValue; } } } return this; }; // 数字数组由大到小排序 Array.prototype.Max2Min = function() { var oValue; for (var i = 0; i < this.length; i++) { for (var j = 0; j <= i; j++) { if (this[i] > this[j]) { oValue = this[i]; this[i] = this[j]; this[j] = oValue; } } } return this; }; // 获得数字数组中最大项 Array.prototype.GetMax = function() { var oValue = 0; for (var i = 0; i < this.length; i++) { if (this[i] > oValue) { oValue = this[i]; } } return oValue; }; // 获得数字数组中最小项 Array.prototype.GetMin = function() { var oValue = 0; for (var i = 0; i < this.length; i++) { if (this[i] < oValue) { oValue = this[i]; } } return oValue; }; // 获取当前时间的中文形式 Date.prototype.GetCNDate = function() { var oDateText = ''; oDateText += this.getFullYear().LenWithZero(4) + new Number(24180).ChrW(); oDateText += this.getMonth().LenWithZero(2) + new Number(26376).ChrW(); oDateText += this.getDate().LenWithZero(2) + new Number(26085).ChrW(); oDateText += this.getHours().LenWithZero(2) + new Number(26102).ChrW(); oDateText += this.getMinutes().LenWithZero(2) + new Number(20998).ChrW(); oDateText += this.getSeconds().LenWithZero(2) + new Number(31186).ChrW(); oDateText += new Number(32).ChrW() + new Number(32).ChrW() + new Number(26143).ChrW() + new Number(26399).ChrW() + new String('26085199682010819977222352011620845').substr(this.getDay() * 5, 5).ToInt().ChrW(); return oDateText; }; //扩展Date格式化 Date.prototype.Format = function(format) { var o = { "M+": this.getMonth() + 1, //月份 "d+": this.getDate(), //日 "h+": this.getHours() % 12 == 0 ? 12 : this.getHours() % 12, //小时 "H+": this.getHours(), //小时 "m+": this.getMinutes(), //分 "s+": this.getSeconds(), //秒 "q+": Math.floor((this.getMonth() + 3) / 3), //季度 "S": this.getMilliseconds() //毫秒 }; var week = { "0": "u65e5", "1": "u4e00", "2": "u4e8c", "3": "u4e09", "4": "u56db", "5": "u4e94", "6": "u516d" }; if (/(y+)/.test(format)) { format = format.replace(RegExp.$1, (this.getFullYear() + "").substr(4 - RegExp.$1.length)); } if (/(E+)/.test(format)) { format = format.replace(RegExp.$1, ((RegExp.$1.length > 1) ? (RegExp.$1.length > 2 ? "u661fu671f" : "u5468") : "") + week[this.getDay() + ""]); } for (var k in o) { if (new RegExp("(" + k + ")").test(format)) { format = format.replace(RegExp.$1, (RegExp.$1.length == 1) ? (o[k]) : (("00" + o[k]).substr(("" + o[k]).length))); } } return format; } Date.prototype.Diff = function(interval, objDate) { //若参数不足或 objDate 不是日期类型則回传 undefined if (arguments.length < 2 || objDate.constructor != Date) { return undefined; } switch (interval) { //计算秒差 case 's': return parseInt((objDate - this) / 1000); //计算分差 case 'n': return parseInt((objDate - this) / 60000); //计算時差 case 'h': return parseInt((objDate - this) / 3600000); //计算日差 case 'd': return parseInt((objDate - this) / 86400000); //计算周差 case 'w': return parseInt((objDate - this) / (86400000 * 7)); //计算月差 case 'm': return (objDate.getMonth() + 1) + ((objDate.getFullYear() - this.getFullYear()) * 12) - (this.getMonth() + 1); //计算年差 case 'y': return objDate.getFullYear() - this.getFullYear(); //输入有误 default: return undefined; } }; //检测是否为空 Object.prototype.IsNullOrEmpty = function() { var obj = this; var flag = false; if (obj == null || obj == undefined || typeof (obj) == 'undefined' || obj == '') { flag = true; } else if (typeof (obj) == 'string') { obj = obj.trim(); if (obj == '') {//为空 flag = true; } else {//不为空 obj = obj.toUpperCase(); if (obj == 'NULL' || obj == 'UNDEFINED' || obj == '{}') { flag = true; } } } else { flag = false; } return flag;