自动获取代理IP信息的例子，含代码，分享哦，

/// <summary>
/// 读取URL数据内容
/// </summary>
/// <param name="url">网址</param>
/// <returns>网站文本内容</returns>
public string HttpGetText(string url)
{
HttpWebRequest Request = (HttpWebRequest)HttpWebRequest.Create(url);
Request.Method = "GET";
Request.ContentType = @"application/x-www-form-urlencoded";
Request.Accept = @"text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8";
Request.Headers.Add(HttpRequestHeader.AcceptLanguage, @"Accept-Language:zh-CN,zh;q=0.8");
Request.UserAgent = @"Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.221 Safari/537.36 SE 2.X MetaSr 1.0";
Request.Proxy = proxy;
var stream = Request.GetResponse().GetResponseStream();
var read = new StreamReader(stream);
var json = read.ReadToEnd();
read.Close();
stream.Close();

System.Diagnostics.Debug.WriteLine("".PadRight(20, '='));
System.Diagnostics.Debug.WriteLine(json);
System.Diagnostics.Debug.WriteLine("".PadRight(20, '='));
return json;
}

public class IPs {
public List<proxy> items = new List<proxy>();

public class proxy {
public string ip;
public int port;
public string address;
public int speed;
public int life;//持续分钟数
public DateTime check_time;
}
}
private void button1_Click(object sender, EventArgs e)
{
var html= HttpGetText("http://www.xicidaili.com/nt");
int i1= html.IndexOf("<table id=\"ip_list\">");
int i2= html.IndexOf("</table>");
string ip_list = html.Substring(i1, i2 - i1+ "</table>".Length);
var find = new Regex(@"<tr.*?>\s*?<td.*?>.*?</td>\s*?<td.*?>(?<ip>.*?)</td>\s*?<td.*?>(?<port>.*?)</td>\s*?<td.*?>\s*?<a.*?>(?<address>.*?)</a>\s*?</td>.*?width:(?<speed>.*?)%.*?<td>(?<life>.*?)</td>.*?<td>(?<check_time>.*?)</td>.*?</tr>", RegexOptions.IgnoreCase | RegexOptions.Singleline);
var ips= find.Matches(ip_list);
listView1.BeginUpdate();
foreach (System.Text.RegularExpressions.Match item in ips) {
try
{
var ip = new IPs.proxy();
ListViewItem lvi = new ListViewItem(item.Groups["ip"].Value); ip.ip = item.Groups["ip"].Value;
lvi.SubItems.Add(item.Groups["port"].Value); ip.port = Convert.ToInt32(item.Groups["port"].Value);
lvi.SubItems.Add(item.Groups["address"].Value); ip.address = item.Groups["address"].Value;
lvi.SubItems.Add(item.Groups["speed"].Value); ip.speed = Convert.ToInt32(item.Groups["speed"].Value);
lvi.SubItems.Add(item.Groups["life"].Value); ip.life = conv(item.Groups["life"].Value);
lvi.SubItems.Add(item.Groups["check_time"].Value); ip.check_time = Convert.ToDateTime(item.Groups["check_time"].Value);
listView1.Items.Add(lvi);
IPaddress.items.Add(ip);
}
catch {
LogAdd("转换IP地址信息出错 " + item.Value);
}
}
listView1.EndUpdate();
int conv(string life) {
int a = 1;
if (life.Contains("天")) {
a = 60 * 24;
life = life.Replace("天", "");
}else if (life.Contains("分钟"))
{
a =1;
life = life.Replace("分钟", "");
}
else if (life.Contains("小时"))
{
a = 60;
life = life.Replace("小时", "");
}
return Convert.ToInt32(life)*a;
}
}

　　

关键代码就是获取指定网页里的IP代理信息，然后用正则表达式提取出来

本来想着直接将html转换为xml，谁知它网页写的不标准，转换不成功

只有用正则来查找了，效果不错~

代码运行环境： vs2017

当然老版本也可以，将局部函数代码放到外部即可。

效果图：



关键代码部分：

var html= HttpGetText("http://www.xicidaili.com/nt");
int i1= html.IndexOf("<table id=\"ip_list\">");
int i2= html.IndexOf("</table>");
string ip_list = html.Substring(i1, i2 - i1+ "</table>".Length);
var find = new Regex(@"<tr.*?>\s*?<td.*?>.*?</td>\s*?<td.*?>(?<ip>.*?)</td>\s*?<td.*?>(?<port>.*?)</td>\s*?<td.*?>\s*?<a.*?>(?<address>.*?)</a>\s*?</td>.*?width:(?<speed>.*?)%.*?<td>(?<life>.*?)</td>.*?<td>(?<check_time>.*?)</td>.*?</tr>", RegexOptions.IgnoreCase | RegexOptions.Singleline);
var ips= find.Matches(ip_list);

　　正则表达式推荐一个网址及学习工具：
http://deerchao.net/tutorials/regex/regex.htm#charclass
我本人也记不住 正则表达式 ，需要用的时候现查。