JavaScript常用字符串与数组扩展函数小结

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!