网络抓取邮箱

namespace WindowsFormsApplication5
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            WebClient wc = new WebClient();//定义一个新的
            wc.Encoding = Encoding.Default;//定义他的格式，防止除乱码
            string url = textBox1.Text.Trim();//定义一个接收文本一的内容
            //if (string.IsNullOrEmpty(url))
            //{
            //    return;
            //}
            string html = wc.DownloadString(url);
            MatchCollection mc = Regex.Matches(html, @"[a-zA-Z0-9_\-\.]+@\w+(\.\w+)+");//邮箱的正则表达式
            StringBuilder sb = new StringBuilder();
            foreach (Match m in mc)
            {
                sb.AppendLine(m.Value);
            }
            textBox2.Text = sb.ToString();
            //File.WriteAllText(@"E:\1.txt", sb.ToString());
          StreamWriter sw = new StreamWriter(@"E:\1.txt",true);
            sw.WriteLine(sb.ToString());
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

    }