远程下载文件源码

/********** 小文件************/
Response.ClearContent();
Response.ClearHeaders();
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", "attachment; filename=logo.gif");
System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.WebRequest.Create("http://dotnet.aspx.cc/Images/logoSite.gif");
System.Net.HttpWebResponse response = (System.Net.HttpWebResponse)request.GetResponse();
Stream stream = response.GetResponseStream();
byte[] bytes = new byte[response.ContentLength];
stream.Read(bytes, 0, Convert.ToInt32(response.ContentLength));
HttpContext.Current.Response.BinaryWrite(bytes);
Response.Flush();
Response.Close();

/********** 大文件************/
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://www.xljsf.com//admin/UploadFile/20076222121122.wma");
request.Timeout = 150000;

HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream stream = response.GetResponseStream();

Response.Clear();
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", "attachment;filename=20076222121122.wma");

int buffer = 1024;
while (true)
{
  byte[] bytes = new byte[buffer];
  int alreadyRead = stream.Read(bytes, 0, buffer);
  if (alreadyRead == 0) break;
  if (alreadyRead == buffer)
    Response.BinaryWrite(bytes);
  else
  {
    byte[] lastBytes = new byte[alreadyRead];
    for (int i = 0; i < alreadyRead; i++)
      lastBytes[i] = bytes[i];
    Response.BinaryWrite(lastBytes);
  }
}
Response.End();