C#抓取网页数据

string tempurl = "xxxx";    //需要请求的页面url
HttpWebRequest webr = (HttpWebRequest)WebRequest.Create(tempurl);//创建请求

string paramStr = "xxx";    //需要传参
byte[] paramByte = Encoding.UTF8.GetBytes(paramStr);

webr.Method = "POST";
webr.ContentLength = paramByte.Length;
webr.ContentType = "application/x-www-form-urlencoded";

Stream strStream = webr.GetRequestStream();
strStream.Write(paramByte, 0, paramByte.Length);

HttpWebResponse wb = (HttpWebResponse)webr.GetResponse();
Stream sr = wb.GetResponseStream();//得到返回数据流
StreamReader sr1 = new StreamReader(sr, Encoding.GetEncoding("utf-8"));//用于读取数据流的内容
string zz = sr1.ReadToEnd();//读取完成
sr1.Close();
strStream.Close();

wb.Close();//关闭