正则表达式学习札记(5):分组、捕获性分组和非捕获性分组

正则表达式学习笔记(5):分组、捕获性分组和非捕获性分组
原帖地址
http://www.blogjava.net/ycyk168/archive/2009/10/25/299659.html
        }

4、一个简单的写法：

JavaScript:
    <script type="text/javascript">
    <!--
        window.onload = function(){
            var now = "25/10/2009";
            alert(now.replace(/(\d\d)\/(\d\d)\/(\d\d\d\d)/,"$3-$2-$1")); //2009-10-25
        }
    //-->
    </script> 

Java:
String now = "25/10/2009";
        System.out.println(now.replaceAll("(\\d\\d)/(\\d\\d)/(\\d\\d\\d\\d)", "$3-$2-$1"));

5、分组结果量词使用
   上文提到，分组是可以结合量词使用的，所以上面的程序也可以这样来写：
   JavaScript;
<script type="text/javascript">
    <!--
        window.onload = function(){
            var now = "25/10/2009";
            alert(now.replace(/(\d{2})\/(\d{2})\/(\d{4})/,"$3-$2-$1")); //2009-10-25
        }
    //-->
    </script> 

Java:

      String now = "25/10/2009";
        System.out.println(now.replaceAll("(\\d{2})/(\\d{2})/(\\d{4})", "$3-$2-$1"));