从网络上下载数据

/// <summary>
/// 售房网下载数据
/// </summary>
/// <param name="url"></param>
/// <returns></returns>
public static string GetResponseString(string url)
{
string _StrResponse = "";
HttpWebRequest _WebRequest = (HttpWebRequest)WebRequest.Create(url);
_WebRequest.UserAgent = "MOZILLA/4.0 (COMPATIBLE; MSIE 7.0; WINDOWS NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648; .NET CLR 3.5.21022; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)";
_WebRequest.AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip;//自动解压
_WebRequest.Method = "GET";
WebResponse _WebResponse = _WebRequest.GetResponse();
StreamReader _ResponseStream = new StreamReader(_WebResponse.GetResponseStream(), System.Text.Encoding.GetEncoding("GBK"));
_StrResponse = _ResponseStream.ReadToEnd();
_WebResponse.Close();
_ResponseStream.Close();
return _StrResponse;
}

 

//发送post请求

public void ProcessRequest(HttpContext context)

        {
 

            HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create("http://fanyi.baidu.com/transcontent");
 

            Encoding encoding = Encoding.UTF8;
 

            string param = "ie=utf-8&source=txt&query=hello&t=1327829764203&token=8a7dcbacb3ed72cad9f3fb079809a127&from=auto&to=auto";
 

            //encoding.GetBytes(postData);
 

            byte[] bs = Encoding.ASCII.GetBytes(param);
 

            string responseData = String.Empty;           
 

            req.Method = "POST";
 

            req.ContentType = "application/x-www-form-urlencoded";
 

            req.ContentLength = bs.Length;
 

            using (Stream reqStream = req.GetRequestStream())//发送post请求
 

            {
 

                reqStream.Write(bs, 0, bs.Length);
 

                reqStream.Close();
 

            }
 

            using (HttpWebResponse response = (HttpWebResponse)req.GetResponse())
 

            {
 

                using (StreamReader reader = new StreamReader(response.GetResponseStream(),encoding))
 

                {
 

                    responseData = reader.ReadToEnd().ToString();
 

                }
 

                context.Response.Write(responseData);
 

            }
 

        }
 
 
 
//保存文件
WebRequest request = WebRequest.Create("url地址");

WebResponse response = request.GetResponse();
Stream reader = response.GetResponseStream();
FileStream writer = new FileStream(" 保存文件的绝对路径", FileMode.OpenOrCreate, FileAccess.Write);
byte[] buff = new byte[512];
int c = 0; //实际读取的字节数
while ((c = reader.Read(buff, 0, buff.Length)) > 0)
{

writer.Write(buff, 0, c);
}
writer.Close();
writer.Dispose();
reader.Close();
reader.Dispose();
response.Close();