正则之replace的三个小示例



将小写转化成大写

 <script>
     var str="356";
     var a=["零","壹","贰","叁","肆","伍","陆","柒","捌","玖"];
     var result=str.replace(/\d/g,function(str,i){
     return ""+a[str];  
                                                                   })
  alert(result); 
    </script>

       结果：叁伍陆

将对应位置替换该替换的东西

 <script>
        var str="My name is{0}.I am{1} years old.I am in class{2} grade{3}.";
        var a=["红红",18,4,6];
        var result=str.replace(/{(\d)}/g,function(str,i){
            return " "+a[i]; 
                                                                           })
        alert(result)
    </script>

      结果：My name is  红红.I am 18 years old.I am in class 4 grade 6.

求a替换的总次数

  <script>
        var str="abcda98apaaa9a";
       var i=0;
       var result=str.replace(/a/g,function(s){
          ++i;
          return s;
   
                                                                })
   alert(i);
    </script>

      结果：7