C#基于正则表达式抓取a标签链接和innerhtml的方法

//读取网页html
string text = File.ReadAllText(Environment.CurrentDirectory + "//test.txt", Encoding.GetEncoding("gb2312"));
string prttern = "<a(\\s+(href=\"(?<url>([^\"])*)\"|'([^'])*'|\\w+=\"(([^\"])*)\"|'([^'])*'))+>(?<text>(.*?))</a>";
var maths = Regex.Matches(text, prttern);
//抓取出来写入的文件
using (FileStream w = new FileStream(Environment.CurrentDirectory + "//wirter.txt", FileMode.Create))
{
    for (int i = 0; i < maths.Count; i++)
    {
      byte[] bs = Encoding.UTF8.GetBytes(string.Format("链接地址:{0},  innerhtml：{1}", maths[i].Groups["url"].Value,
        maths[i].Groups["text"].Value) + "\r\n");
      w.Write(bs, 0, bs.Length);
      Console.WriteLine();
    }
}
Console.ReadKey();

string text =File.ReadAllText(Environment.CurrentDirectory + "//test.txt", Encoding.GetEncoding("gb2312"));
string prttern = "<img(\\s*(src=\"(?<src>[^\"]*?)\"|data-url=\"(?<dataurl>[^\"]*?)\"|[-\\w]+=\"[^\"]*?\"))*\\s*/>";
var maths = Regex.Matches(text, prttern);
//抓取出来写入的文件
using (FileStream w = new FileStream(Environment.CurrentDirectory + "//wirter.txt", FileMode.Create))
{
    for (int i = 0; i < maths.Count; i++)
    {
      byte[] bs = Encoding.UTF8.GetBytes(string.Format("图片src:{0},  图片data-url：{1}", maths[i].Groups["src"].Value,
        maths[i].Groups["dataurl"].Value) + "\r\n");
      w.Write(bs, 0, bs.Length);
      Console.WriteLine();
    }
}