String对象的扩展函数：
String.prototype.trim = function() { return this.replace(/^/s+|/s+$/g,""); } String.prototype.ltrim = function() { return this.replace(/^/s+/g,""); } String.prototype.rtrim = function() { return this.replace(//s+$/g,""); } String.prototype.splitAndTrim = function($delimiter, $limit) { var $ss = this.split($delimiter, $limit); for(var $i=0; $i<$ss.length; $i++) $ss[$i] = $ss[$i].trim(); return $ss; } String.prototype.htmlEntities = function () { return this.replace(/&/g,'&').replace(/</g,'<').replace(/>/g,'>'); } String.prototype.stripTags = function () { return this.replace(/<([^>]+)>/g,''); } String.prototype.toArray = function() { return this.split(''); } String.prototype.toIntArray = function() { var returnArray = []; for (var i=0; i<this.length; i++) { returnArray.push(this.charCodeAt(i)); } return returnArray; } String.prototype.replaceAll = function($old, $snew){ return this.replace(new RegExp($old,"gm"),$snew); } 变量替换
var a = "I Love {0}, and You Love {1},Where are {0}!";a.format("You","Me"); String.prototype.format = function(){ var args = arguments; return this.replace(//{(/d+)/}/g,function(m,i,o,n){ return args[i]; }); } 在字符串末尾追加字符串
String.prototype.append = function($str){ return this.concat($str); } 删除指定索引位置的字符，索引无效将不删除任何字符
String.prototype.deleteCharAt = function($sIndex){ if($sIndex<0 || $sIndex>=this.length){ return this.valueOf(); }else if($sIndex==0){ return this.substring(1,this.length); }else if($sIndex==this.length-1){ return this.substring(0,this.length-1); }else{ return this.substring(0,$sIndex)+this.substring($sIndex+1); } } 删除指定索引间的字符串.$sIndex和$eIndex所在的字符不被删除！依赖deleteCharAt
String.prototype.deleteString = function($sIndex, $eIndex){ if($sIndex==$eIndex){ return this.deleteCharAt($sIndex); }else{ if($sIndex>$eIndex){ var tIndex=$eIndex; $eIndex=$sIndex; $sIndex=tIndex; } if($sIndex<0)$sIndex=0; if($eIndex>this.length-1)$eIndex=this.length-1; return this.substring(0,$sIndex+1)+this.substring($eIndex,this.length); } } 检查字符串是否以某个字符串(str)结尾
String.prototype.endsWith = function($str){ return this.substr(this.length - $str.length) == $str; } 检查该字符串是否以某个字符串开始
String.prototype.startsWith = function(str){ return this.substr(0, str.length) == str; } 比较两个字符串是否相等，不区分大小写!
String.prototype.equalsIgnoreCase = function($str){ if(this.length!=$str.length){ return false; }else{ var tmp1=this.toLowerCase(); var tmp2=$str.toLowerCase(); return tmp1==tmp2; } } 将指定的字符串插入到指定的位置后面!索引无效将直接追加到字符串的末尾
String.prototype.insert = function($ofset, $str){ if($ofset<0 || $ofset>=this.length-1){ return this.concat($str); } return this.substring(0,$ofset)+$str+this.substring($ofset+1); } 将指定的位置的字符设置为另外指定的字符或字符串.索引无效将直接返回不做任何处理！
String.prototype.setCharAt = function($ofset, $str){ if($ofset<0 || $ofset>=this.length-1){ return this.valueOf(); } return this.substring(0,$ofset)+$str+this.substring($ofset+1); } String.prototype.replaceLen = function(start, len, replaced) { if(!len) return this; if(start >= this.length) return this; var returnSeg = ''; var returnSeg2 = ''; var i = 0; for (; i < this.length; i++){ var c = this.charAt(i); if(i < start) returnSeg += c; if(i >= start + len) returnSeg2 += c; } return returnSeg + replaced + returnSeg2; } 扩展基础类：
替换字符，这个在替换填入比较有用，比如***天***小时 替换为 <input />天<input />小时
String.prototype.replaceChar = function(target, replaced, start) { if(!target) return this; if(!start) start = 0; var returnVal = this.substring(0, start); var index = 0; for (var i = start; i < this.length; i++) { var c = this.charAt(i); target = typeof target == 'function' ? target.call(this, index) : target; if (c == target) { returnVal += typeof replaced == 'function' ? replaced.call(this, index) : replaced; while (i < this.length - 1 && this.charAt(i + 1) == c) { i++; } index++; }else{ returnVal += c; } } return returnVal; } 将该字符串反序排列
String.prototype.reverse = function(){ var str=""; for(var i=this.length-1;i>=0;i--){ str=str.concat(this.charAt(i)); } return str; } 计算长度，每个汉字占两个长度，英文字符每个占一个长度
String.prototype.ucLength = function(){ var len = 0; for(var i=0;i<this.length;i++){ if(this.charCodeAt(i)>255)len+=2; else len++; } return len; } 在字符串的左边填充一些特定的字符
String.prototype.lpad = function(len, s) { var a = new Array(this); var n = (len - this.length); for ( var i = 0; i < n; i++) { a.unshift(s); } return a.join(""); } 在字符串的右边填充一些特定的字符
String.prototype.rpad = function(len, s) { var a = new Array(this); var n = (len - this.length); for ( var i = 0; i < n; i++) { a.push(s); } return a.join(""); } 把字符串的首字母转化为大写
String.prototype.ucwords = function() { return this.substring(0,1).toUpperCase().concat(this.substring(1)); } String.prototype.contains = function($str) { return this.indexOf($str) > -1 ? true : false; } 将格式为2008-04-02 10:08:44的字符串转成日期(String对象的值必须为: 2008-04-02 10:08:44)
String.prototype.toDate = function(){ var str = this.replace(/-/g,"/"); return (new Date(str)); } 将原来用字符串表示的十进数转成十进制浮点数: precision为精度
String.prototype.toFloat = function(precision){ precision = precision || 2; return parseFloat(this,10).toFixed(precision); } 将原来用字符串表示的十进数转成十进制整数
String.prototype.toInt = function(){ return parseInt(this,10).toString(); } 将两个原来用字符串表示的十进数相加后当作字串返回 : addend为加数
String.prototype.add = function(addend){ var sum = parseFloat(this,10) + parseFloat(addend,10); return sum+""; } 十进制转其他进制代码如下nextScale为进制 如2,8,16
String.prototype.shiftScale = function(nextScale){ return parseFloat(this).toString(nextScale); } 各进制互相转换 ：
this对象必须是整数
@param preScale 原是是几进制数
@param nextScale 要转换成几进制数
String.prototype.scaleShift = function(preScale,nextScale){ return parseInt(this,preScale).toString(nextScale); } 全角2半角 document.write("ＡＢＣ １２３，我们都是好朋友");
String.prototype.dbc2sbc = function (){
return this.replace(/[/uff01-/uff5e]/g,function(a){return String.fromCharCode(a.charCodeAt(0)-65248);}).replace(//u3000/g," ");
}
Array扩展函数：
var isNumeric = function(x) { // returns true if x is numeric and false if it is not. var RegExp = /^(-)?(/d*)(/.?)(/d*)$/; return String(x).match(RegExp); } var myArray = [1,'two',3,'four',5,'six',7,'eight',9,'ten']; var oddArray=myArray.filter(isNumeric); // outputs: 1,3,5,7,9 var oddArray=myArray.some(isNumeric); // outputs: true var oddArray=myArray.every(isNumeric); // outputs: false var printArray =function(x, idx){ document.writeln('['+idx+'] = '+x); } myArray.forEach(printArray);// outputs: [0] = 1 [1] = two [2] = 3 [3] = four [4] = 5 myArray.remove(9); document.writeln(myArray); if (!Array.prototype.every) { Array.prototype.every = function(fun /*, thisp*/) { var len = this.length; if (typeof fun != "function") throw new TypeError(); var thisp = arguments[1]; for (var i = 0; i < len; i++) { if (i in this && !fun.call(thisp, this[i], i, this)) return false; } return true; }; } if (!Array.prototype.filter) { Array.prototype.filter = function(fun /*, thisp*/) { var len = this.length; if (typeof fun != "function") throw new TypeError(); var res = new Array(); var thisp = arguments[1]; for (var i = 0; i < len; i++) { if (i in this) { var val = this[i]; // in case fun mutates this if (fun.call(thisp, val, i, this)) res.push(val); } } return res; }; } if (!Array.prototype.forEach) { Array.prototype.forEach = function(fun /*, thisp*/) { var len = this.length; if (typeof fun != "function") throw new TypeError(); var thisp = arguments[1]; for (var i = 0; i < len; i++) { if (i in this) fun.call(thisp, this[i], i, this); } }; } if (!Array.prototype.map) { Array.prototype.map = function(fun /*, thisp*/) { var len = this.length; if (typeof fun != "function") throw new TypeError(); var res = new Array(len); var thisp = arguments[1]; for (var i = 0; i < len; i++) { if (i in this) res[i] = fun.call(thisp, this[i], i, this); } return res; }; } if (!Array.prototype.some) { Array.prototype.some = function(fun /*, thisp*/) { var len = this.length; if (typeof fun != "function") throw new TypeError(); var thisp = arguments[1]; for (var i = 0; i < len; i++) { if (i in this && fun.call(thisp, this[i], i, this)) return true; } return false; }; } Array.prototype.sortNum = function() { return this.sort( function (a,b) { return a-b; } ); } <!-- var tmp = [5,9,12,18,56,1,10,42,'blue',30, 7,97,53,33,30,35,27,30,'35','Ball', 'bubble']; var thirty=tmp.find(30); // Returns 9, 14, 17 var thirtyfive=tmp.find('35'); // Returns 18 var thirtyfive=tmp.find(35); // Returns 15 var haveBlue=tmp.find('blue'); // Returns 8 var notFound=tmp.find('not there!'); // Returns false var regexp1=tmp.find(/^b/); // returns 8,20 (first letter starts with b) var regexp1=tmp.find(/^b/i); // returns 8,19,20 (same as above but ignore case) --> Array.prototype.find = function(searchStr) { var returnArray = false; for (i=0; i<this.length; i++) { if (typeof(searchStr) == 'function') { if (searchStr.test(this[i])) { if (!returnArray) { returnArray = [] } returnArray.push(i); } } else { if (this[i]===searchStr) { if (!returnArray) { returnArray = [] } returnArray.push(i); } } } return returnArray; } 随机改变数组的排序
Array.prototype.shuffle = function (){ for(var rnd, tmp, i=this.length; i; rnd=parseInt(Math.random()*i), tmp=this[--i], this[i]=this[rnd], this[rnd]=tmp); return this; } <!--var myArray = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]; var yourArray = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]; document.writeln(myArray.compare(yourArray)); // outputs: true;--> Array.prototype.compare = function(testArr) { if (this.length != testArr.length) return false; for (var i = 0; i < testArr.length; i++) { if (this[i].compare) { if (!this[i].compare(testArr[i])) return false; } if (this[i] !== testArr[i]) return false; } return true; } 去掉数组中重复的值var a = new Array("5","7","7"); a.unique();
Array.prototype.unique = function() { var data = this || []; var a = {}; //声明一个对象，javascript的对象可以当哈希表用 for (var i = 0; i < data.length; i++) { a[data[i]] = true; //设置标记，把数组的值当下标，这样就可以去掉重复的值 } data.length = 0; for (var i in a) { //遍历对象，把已标记的还原成数组 this[data.length] = i; } return data; } Array.prototype.addAll = function($array) { if($array == null || $array.length == 0) return; for(var $i=0; $i<$array.length; $i++) this.push($array[$i]); } Array.prototype.contains = function($value) { for(var $i=0; $i<this.length; $i++) { var $element = this[$i]; if($element == $value) return true; } return false; } Array.prototype.indexOf = function($value) { for(var $i=0; $i<this.length; $i++) { if(this[$i] == $value) return $i; } return -1; } if (!Array.prototype.lastIndexOf) { Array.prototype.lastIndexOf = function(elt /*, from*/) { var len = this.length; var from = Number(arguments[1]); if (isNaN(from)) { from = len - 1; } else { from = (from < 0) ? Math.ceil(from) : Math.floor(from); if (from < 0) from += len; else if (from >= len) from = len - 1; } for (; from > -1; from--) { if (from in this && this[from] === elt) return from; } return -1; }; } Array.prototype.insertAt = function($value, $index) { if($index < 0) this.unshift($value); else if($index >= this.length) this.push($value); else this.splice($index, 0, $value); } 根据数组的下标来删除元素
Array.prototype.removeByIndex=function($n) { if($n<0){ //如果n<0，则不进行任何操作。 return this; }else{ return this.slice(0,$n).concat(this.slice($n+1,this.length)); } } 依赖indexOf
Array.prototype.remove = function($value) { var $index = this.indexOf($value); if($index != -1) this.splice($index, 1); } Array.prototype.removeAll = function() { while(this.length > 0) this.pop(); } Array.prototype.replace = function($oldValue, $newValue) { for(var $i=0; $i<this.length; $i++) { if(this[$i] == $oldValue) { this[$i] = $newValue; return; } } } Array.prototype.swap = function($a, $b) { if($a == $b) return; var $tmp = this[$a]; this[$a] = this[$b]; this[$b] = $tmp; } Array.prototype.max = function() { return Math.max.apply({}, this); } Array.prototype.min = function() { return Math.min.apply({}, this); } Array.prototype.splice = function(start, delLen, item){ var len =this.length; start = start<0?0:start>len?len:start?start:0; delLen=delLen<0?0:delLen>len?len:delLen?delLen:len; var arr =[],res=[]; var iarr=0,ires=0,i=0; for(i=0;i<len;i++){ if(i<start|| ires>=delLen) arr[iarr++]=this[i]; else { res[ires++]=this[i]; if(item&&ires==delLen){ arr[iarr++]=item; } } } if(item&&ires<delLen) arr[iarr]=item; for(var i=0;i<arr.length;i++){ this[i]=arr[i]; } this.length=arr.length; return res; } Array.prototype.shift = function(){ if(!this) return[];return this.splice(0,1)[0];} 分开添加,关键字shallow copy,如果遇到数组，复制数组中的元素
Array.prototype.concat = function(){ var i=0; while(i<arguments.length){ if(typeof arguments[i] === 'object'&&typeof arguments[i].splice ==='function' &&!arguments[i].propertyIsEnumerable('length')){ // NOT SHALLOW COPY BELOW // Array.prototype.concat.apply(this,arguments[i++]); var j=0; while(j<arguments[i].length) this.splice(this.length,0,arguments[i][j++]); i++; } else{ this[this.length]=arguments[i++]; } } return this; } Array.prototype.join = function(separator){ var i=0,str=""; while(i<this.length) str+=this[i++]+separator; return str; } Array.prototype.pop = function() { return this.splice(this.length-1,1)[0];} Array.prototype.push = function(){ Array.prototype.splice.apply(this, [this.length,0].concat(Array.prototype.slice.apply(arguments))); //这里没有直接处理参数，而是复制了一下 return this.length; } Array.prototype.reverse = function(){ for(var i=0;i<this.length/2;i++){ var temp = this[i]; this[i]= this[this.length-1-i]; this[this.length-1-i] = temp; } return this; } Array.prototype.slice = function(start, end){ var len =this.length; start=start<0?start+=len:start?start:0; end =end<0?end+=len:end>len?len:end?end:len; var i=start; var res = []; while(i<end){ res.push(this[i++]); } return res; } //arr.unshift(ele1,ele2,ele3....) Array.prototype.unshift =function(){ Array.prototype.splice.apply(this,[0,0].concat(Array.prototype.slice.apply(this,arguments))); }