FtpWebResponse.ContentLength Property
Definition
Important
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Gets the length of the data received from the FTP server.
public:
virtual property long ContentLength { long get(); };public override long ContentLength { get; }member this.ContentLength : int64Public Overrides ReadOnly Property ContentLength As LongProperty Value
An Int64 value that contains the number of bytes of data received from the FTP server.
Examples
The following code example downloads a file from on the specified FTP server. This property contains the number of bytes in the downloaded file.
static bool DownloadFileFromServer( Uri^ serverUri, String^ localFileName )
{
// The serverUri parameter should start with the ftp:// scheme.
if ( serverUri->Scheme != Uri::UriSchemeFtp )
{
return false;
}
// Get the object used to communicate with the server.
// Note that the cast to FtpWebRequest is done only
// for the purposes of illustration. If your application
// does not set any properties other than those defined in the
// System.Net.WebRequest class, you can use the following line instead:
// WebRequest request = WebRequest.Create(serverUri);
//
FtpWebRequest^ request = dynamic_cast<FtpWebRequest^>(WebRequest::Create( serverUri ));
request->Method = WebRequestMethods::Ftp::DownloadFile;
FtpWebResponse^ response = dynamic_cast<FtpWebResponse^>(request->GetResponse());
Stream^ responseStream = nullptr;
StreamReader^ readStream = nullptr;
StreamWriter^ writeStream = nullptr;
try
{
responseStream = response->GetResponseStream();
readStream = gcnew StreamReader( responseStream,System::Text::Encoding::UTF8 );
// Display information about the data received from the server.
Console::WriteLine( "Bytes received: {0}", response->ContentLength );
Console::WriteLine( "Message from server: {0}", response->StatusDescription );
Console::WriteLine( "Resource: {0}", response->ResponseUri );
// Write the bytes received from the server to the local file.
if ( readStream != nullptr )
{
writeStream = gcnew StreamWriter( localFileName,false );
writeStream->Write( readStream->ReadToEnd() );
}
}
finally
{
if ( readStream != nullptr )
{
readStream->Close();
}
if ( response != nullptr )
{
response->Close();
}
if ( writeStream != nullptr )
{
writeStream->Close();
}
}
return true;
}
public static bool DownloadFileFromServer(Uri serverUri, string localFileName)
{
// The serverUri parameter should start with the ftp:// scheme.
if (serverUri.Scheme != Uri.UriSchemeFtp)
{
return false;
}
// Get the object used to communicate with the server.
// Note that the cast to FtpWebRequest is done only
// for the purposes of illustration. If your application
// does not set any properties other than those defined in the
// System.Net.WebRequest class, you can use the following line instead:
// WebRequest request = WebRequest.Create(serverUri);
//
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverUri);
request.Method = WebRequestMethods.Ftp.DownloadFile;
FtpWebResponse response = (FtpWebResponse) request.GetResponse();
Stream responseStream = null;
StreamReader readStream = null;
StreamWriter writeStream = null;
try
{
responseStream = response.GetResponseStream();
readStream = new StreamReader(responseStream, System.Text.Encoding.UTF8);
// Display information about the data received from the server.
Console.WriteLine("Bytes received: {0}",response.ContentLength);
Console.WriteLine("Message from server: {0}", response.StatusDescription);
Console.WriteLine("Resource: {0}", response.ResponseUri);
// Write the bytes received from the server to the local file.
if (readStream != null)
{
writeStream = new StreamWriter(localFileName, false);
writeStream.Write(readStream.ReadToEnd());
}
}
finally
{
if (readStream != null)
{
readStream.Close();
}
if (response != null)
{
response.Close();
}
if (writeStream != null)
{
writeStream.Close();
}
}
return true;
}
Remarks
When a response stream is returned by the FTP server, the ContentLength property contains the number of bytes in the stream. ContentLength returns −1 if no data was returned in the response or if the server did not send content length information. The return value is greater than or equal to zero if data was or should have been returned. For example, for requests that use the ListDirectory field, the ContentLength property always returns −1. For requests that use the UploadFile method, the ContentLength property is always zero. For requests that use the DownloadFile method, the property is greater than zero if the downloaded file contained data and is zero if it was empty.
For requests that use the GetFileSize method, ContentLength returns the size of the specified file on the server.
