大家好 我想问个关于正则式的问题  下面是原代码,想从当中提出某些内容:
<div id="main">
<h2>Madonna </h2>
<dl>
<dt>Website /dt>
<dd>
                      <a href="http://www.madonna.com/"  title="Go to the Madonna website">www.madonna.com  </a>
</dd>
<dt id="artPhoto">Artist photo </dt>
<dd id="photo"> <img src="images/madonna.jpg" alt="Madonna"  title="Madonna"/> </dd>

想提取当中 id=main的 "Madonna", "www.madonna.com "   和id="photo"的  madonna.jpg这张图片 请问用正则式的话  那表达式应该是怎样的? 请大家帮帮忙,因为刚第1天学正则式,所以比较迷茫, 如果大家关于正则式的好网站的话,麻烦也提供下给小弟多学习学习  谢谢

Java code    String str = "<div id="main">
<h2>Madonna </h2>
<dl>
<dt>Website /dt>
<dd>
<a href="http://www.madonna.com/"  title="Go to the Madonna website">www.madonna.com  </a>
</dd>
<dt id="artPhoto">Artist photo </dt>
<dd id="photo"> <img src="images/madonna.jpg" alt="Madonna"  title="Madonna"/> </dd> ";
    Pattern p = Pattern.compile("<div id="main">.*?<a href="http://(.*?)[/]?".*?<img src="images/(.*?)"", Pattern.DOTALL);
    Matcher m = p.matcher(str);
    while (m.find()) {
      System.out.println(m.group(1));
      System.out.println(m.group(2));
    }

public static void main(String[] args) throws IOException, InterruptedException {
        String s = "<div id="main">
<h2>Madonna </h2>
<dl>
<dt>Website /dt>
<dd>
<a href="http://www.madonna.com/"  title="Go to the Madonna website">www.madonna.com  </a>
</dd>
<dt id="artPhoto">Artist photo </dt>
<dd id="photo"> <img src="images/madonna.jpg" alt="Madonna"  title="Madonna"/> </dd> ";
        Pattern p = Pattern.compile(
            "<div id="main">
<h2>(.*?)</h2>.*?<a href="http://(.*?)[/]?".*?<img src="images/(.*?)"",
            Pattern.DOTALL);
        Matcher m = p.matcher(s);
        while (m.find()) {
            System.out.println(m.group(1));
            System.out.println(m.group(2));
            System.out.println(m.group(3));
        }
    }