JQuery替换全部字符

1   //JQuery替换全部字符
　　　<script>
2      String.prototype.replaceAll = function (targetStr, newStr) {
3        var sourceStr = this.valueOf();
4        while (sourceStr.indexOf(targetStr) !== -1) {
5             sourceStr = sourceStr.replace(targetStr, newStr);
6        }
7        return sourceStr;
8      };
9   </script>