JavaScript常用字符串与数组扩展函数小结

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);   } 

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];   }); } 

String.prototype.append = function($str){   return this.concat($str); } 

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);   } } 

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);   } } 

String.prototype.endsWith = function($str){   return this.substr(this.length - $str.length) == $str; } 

String.prototype.startsWith = function(str){   return this.substr(0, str.length) == str; }  

String.prototype.equalsIgnoreCase = function($str){   if(this.length!=$str.length){     return false;   }else{     var tmp1=this.toLowerCase();     var tmp2=$str.toLowerCase();     return tmp1==tmp2;   } } 

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); } 

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;  } 

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;  }  

String.prototype.reverse = function(){   var str="";   for(var i=this.length-1;i>=0;i--){     str=str.concat(this.charAt(i));   }   return str; } 

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; } 

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(""); } 

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(""); } 

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; } 

String.prototype.toDate = function(){   var str = this.replace(/-/g,"/");   return (new Date(str)); } 

String.prototype.toFloat = function(precision){   precision = precision || 2;   return parseFloat(this,10).toFixed(precision); } 

String.prototype.toInt = function(){   return parseInt(this,10).toString(); } 

String.prototype.add = function(addend){   var sum = parseFloat(this,10) + parseFloat(addend,10);   return sum+""; } 

String.prototype.shiftScale = function(nextScale){   return parseFloat(this).toString(nextScale); } 

String.prototype.scaleShift = function(preScale,nextScale){   return parseInt(this,preScale).toString(nextScale); } 

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; } 

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; } 

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); } 

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));    }  } 

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];} 

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))); }