javascriptの中のRegexpは簡単に分かります.

/*****************  RegExp       ：*********************/

 /*

  * exec() :             。

  			 @param :       ,         

  			 @return :                (array)，           null

         @explain :       Array   ，    2      :

                    index -              

                    input -               

                                       ，                 (       ，          )

 */

  var text = 'gid and var and global';

  var patterns = /gid( and var( and global)?)?/;

  var matches = patterns.exec(text);

  console.log(matches.index);   //0       0          ，       matches index 0

  console.log(matches.input);   //"gid and var and global"               

  console.log(matches[0]);      //"gid and var and global"               

  console.log(matches[1]);      //" and var and global"   ( and var( and global)?)?                   

  console.log(matches[2]);      //" and global"           ( and global)?                  

  console.log(matches[3]);      //undefined                       ， return undefined



  //exec()  ，             (g),             。

  //           ，            exec()              ，

  //     (g) ，            exec()                 

  //{IE lastIndex    g   ，      。}



  var txt = 'cat, bat, sat, fat';

  var patterns1 = /.at/;

  var matches1 = patterns1.exec(txt);

  console.log(matches1.index);            //0  0           

  console.log(matches1[0]);               //cat

  console.log(patterns1.lastIndex);       //0                 。



  matches1 = patterns1.exec(txt);         

  console.log(matches1.index);            //0

  console.log(matches1[0]);               //cat

  console.log(patterns1.lastIndex);       //0



  var patterns2 = /.at/g;

  var matches2 = patterns2.exec(txt);

  console.log(matches2.index);            //0

  console.log(matches2[0]);               //cat

  console.log(patterns2.lastIndex);       //3



  matches2 = patterns2.exec(txt);

  console.log(matches2.index);            //5

  console.log(matches2[0]);               //bat

  console.log(patterns2.lastIndex);       //8



  /*

   * test() 

   * @param : {type:String}   

   * @return : {type:Boolean}

   * @explains :       return true,  return false, 

  */

  var stxt = '000-12-2354';

  var patterns3 = /\d{3}-\d{2}-\d{4}/;

  if(patterns3.test(stxt)){

    console.log("match sucess!")

  }

  /*

   * toLocalString() toString()

   * @return ：             ，             。

  */

  var patterns4 = new RegExp("\\[bc\\]at","gi");

  var patterns5 = /\[bc\]at/gi;

  console.log(patterns4.toLocaleString(),patterns4.toString());   // /\[bc\]at/gi   /\[bc\]at/gi

  console.log(patterns5.toLocaleString(),patterns5.toString());   // /\[bc\]at/gi   /\[bc\]at/gi

 /*****************  RegExp       （                  ）：*********************/

 /*

  *            

  * input           $_                   

  * lastMatch       $&                

  * lastParen       $+                  

  * leftContext     $`        input    lastMatch     

  * multiline       $*           ，                。

  * rightContext    $'         input    lastMatch     

  *                    

  *   ：opera   input、lastMatch、lastParen multiline  

  * IE   multiline  

 */

  var text = 'this has been a short summer';

  var pattern = /(.)hort/g;



  if(pattern.test(text)){

    console.log(RegExp.input + '；','shortAttr：' + RegExp.$_ + '；');//this has been a short summer

    console.log(RegExp.leftContext);    //"this has been a"    short    

    console.log(RegExp.rightContext);   //" summer"            short    

    console.log(RegExp.lastMatch);      //"short"                    

    console.log(RegExp.lastParen);      //"s"                          (.)            

    console.log(RegExp.multiline);      //false;                    

  }



  //         ，             ECMAScript   ，                。

  var text1 = 'this has been a short summer';

  var pattern1 = /(.)hort/g;

  if(pattern1.test(text1)){

    console.log(RegExp["$_"]);      //"this has been a short summer"

    console.log(RegExp["$`"]);      //"this has been a "

    console.log(RegExp["$'"]);      //" summer"

    console.log(RegExp["$&"]);      //short

    console.log(RegExp["$+"]);      //s               (.)            

    console.log(RegExp["$*"]);      //false

  }

  /*

   *         ，    9               。

   *        RegExp.$1、RegExp.$2....RegExp.$9

   *       ，  .....         。   exec(),test()   ，         。

   *     test()       ，RegExp       $1,$2       。

  */

  var text2 = 'this has been a short communication'

  var pattern2 = /(..)ic(...)o(.)/;

  if(pattern2.test(text2)){

    console.log(RegExp.$1);   //un

    console.log(RegExp.$2);   //ati

    console.log(RegExp.$3);   //n

  }

 /*******************************          **********************/

 /*

  * match() 

            @param :     ，       RegExp  。

            @return :       ， exec()  。

  * search(regexp)

            @param : match()    。

            @return :         regexp            。          ；       -1；

            @explain ：             

  * replace(regexp/string,string/function)

            @param :       RegExp         (              )，(             )

            @param ：                   (      )

            @return ：        ，   string/function     regexp/string                 。

            @explain ：         ，           ，       (g)

            @extra :             ，          (      )，                     

    split(string/regexp,Array.length)

            @param :            ，         ，     regexp  

            @param ：        ，               。

            @return : array           。

 */

 var text = 'cat, bat, sat, fat';

 var pattern = /.at/;

 // pattern.exec(text)  

 var matches = text.match(pattern);

 console.log(matches.index);        //0

 console.log(matches[0]);           //cat

 console.log(pattern.lastIndex);    //0



 var text1 = 'sst, bat, sat, fat';

 var pos = text1.search(/at/);

 var pos1 = text1.search(/at/);

 console.log(pos,pos1);             //6 6     bat





 var result = text.replace('at', 'oncat');

 console.log(result);               //concat, bat, sat, fat

 var result1 = text.replace(/at/g, 'fs');

 console.log(result1);              //cfs, bfs, sfs, ffs



 //          ; $1,       ，   (.at)    

 var result2 = text.replace(/(.at)/g, 'fuck[$1]');

 console.log(result2);              //fuck[cat], fuck[bat], fuck[sat], fuck[fat]



 var colorText = "red,blue,green,yellow";

 var r1 = colorText.split(",");

 var r2 = colorText.split("," ,2);

 var r3 = colorText.split(/[^\,]+/);

 console.log(r1);                   //["red", "blue", "green", "yellow"]

 console.log(r2);                   //["red", "blue"]

 console.log(r3);                   //["", ",", ",", ",", ""]