Question

I have zip file in ftp server,this zip file contain more then one xml file in it,i want to download this zipfile and save to local disk,i have write below code,i download file but when i try to Extract this zip it throw me error that File is corrupted……

FtpWebRequest request = (FtpWebRequest)WebRequest.Create(_remoteHost + file);
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.Credentials = new NetworkCredential(_remoteUser, _remotePass);
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
Stream responseStream = response.GetResponseStream();
StreamReader reader = new StreamReader(responseStream);

StreamWriter writer = new StreamWriter(destination);
writer.Write(reader.ReadToEnd());

writer.Close();
reader.Close();
response.Close();

Answer 1

You are channeling the result of the FTP request through a StreamReader. This has the usually beneficial effect of handling character encoding, but is not something you ever want to do when dealing with binary data (i.e. a zip file). Instead, you should read the data directly from the stream. Something like:

FtpWebRequest request = (FtpWebRequest)WebRequest.Create(_remoteHost + file);
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.Credentials = new NetworkCredential(_remoteUser, _remotePass);
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
Stream responseStream = response.GetResponseStream();

// Copy the data from the responseStream to destination 1k at a time (feel free to increase buffer size)
byte[] buffer = new byte[1024];
for (int amountRead = responseStream.Read(buffer, 0, buffer.Length); amountRead > 0; amountRead = responseStream.Read(buffer, 0, buffer.Length))
{
    destination.Write(buffer, 0, amountRead);
}
destination.Flush();

response.Close();