/// <summary>
/// 如果是一个错误将记录ErrorOccurred事件。
/// </summary>
void client_ErrorOccurred(object sender, ErrorEventArgs e)
{
this.lstLog.Items.Add(
string.Format("{0} {1} ", DateTime.Now, e.ErrorException.Message));
var innerException = e.ErrorException.InnerException;
// 记录所有的innerException.
while (innerException != null)
{
this.lstLog.Items.Add(
string.Format("\t\t\t {0} ", innerException.Message));
innerException = innerException.InnerException;
}
this.lstLog.SelectedIndex = this.lstLog.Items.Count - 1;
}
/// <summary>
/// Download a single file directly.
/// </summary>
void DownloadFile(FTPFileSystem file, string localPath)
{
if (file.IsDirectory)
{
throw new ArgumentException(
"The FTPFileSystem to download is a directory in fact");
}
string destPath = localPath + "\\" + file.Name;
// Create a request to the file to be downloaded.
FtpWebRequest request = WebRequest.Create(file.Url) as FtpWebRequest;
request.Credentials = this.manager.Credentials;
// Download file.
request.Method = WebRequestMethods.Ftp.DownloadFile;
FtpWebResponse response = null;
Stream responseStream = null;
MemoryStream downloadCache = null;
try
{
// Retrieve the response from the server and get the response stream.
response = request.GetResponse() as FtpWebResponse;
this.manager.OnNewMessageArrived(new NewMessageEventArg
{
NewMessage = response.StatusDescription
});
responseStream = response.GetResponseStream();
// Cache data in memory.
downloadCache = new MemoryStream(FTPDownloadClient.MaxCacheSize);
byte[] downloadBuffer = new byte[FTPDownloadClient.BufferSize];
int bytesSize = 0;
int cachedSize = 0;
// Download the file until the download is completed.
while (true)
{
// Read a buffer of data from the stream.
bytesSize = responseStream.Read(downloadBuffer, 0,
downloadBuffer.Length);
// If the cache is full, or the download is completed, write
// the data in cache to local file.
if (bytesSize == 0 ||
MaxCacheSize < cachedSize + bytesSize)
{
try
{
// Write the data in cache to local file.
WriteCacheToFile(downloadCache, destPath, cachedSize);
// Stop downloading the file if the download is paused,
// canceled or completed.
if (bytesSize == 0)
{
break;
}
// Reset cache.
downloadCache.Seek(0, SeekOrigin.Begin);
cachedSize = 0;
}
catch (Exception ex)
{
string msg = string.Format(
"There is an error while downloading {0}. "
+ " See InnerException for detailed error. ",
file.Url);
ApplicationException errorException
= new ApplicationException(msg, ex);
// Fire the DownloadCompleted event with the error.
ErrorEventArgs e = new ErrorEventArgs
{
ErrorException = errorException
};
this.manager.OnErrorOccurred(e);
return;
}
}
// Write the data from the buffer to the cache in memory.
downloadCache.Write(downloadBuffer, 0, bytesSize);
cachedSize += bytesSize;
}
var fileDownloadCompletedEventArgs = new FileDownloadCompletedEventArgs
{
LocalFile = new FileInfo(destPath),
ServerPath = file.Url
};
this.OnFileDownloadCompleted(fileDownloadCompletedEventArgs);
}
finally
{
if (response != null)
{
response.Close();
}
if (responseStream != null)
{
responseStream.Close();
}
if (downloadCache != null)
{
downloadCache.Close();
}
}
}
/// <summary>
/// Log the ErrorOccurred event if there was an error.
/// </summary>
void client_ErrorOccurred(object sender, ErrorEventArgs e)
{
this.Invoke(new EventHandler <ErrorEventArgs>(
client_ErrorOccurredHandler), sender, e);
}
/// <summary>
/// 下载一个单一的文件目录.
/// </summary>
void DownloadFile(FTPFileSystem file, string localPath)
{
if (file.IsDirectory)
{
throw new ArgumentException(
"The FTPFileSystem to download is a directory in fact");
}
string destPath = localPath + "\\" + file.Name;
//创建一个要下载的文件的请求.
FtpWebRequest request = WebRequest.Create(file.Url) as FtpWebRequest;
request.Credentials = this.manager.Credentials;
// 下载文件.
request.Method = WebRequestMethods.Ftp.DownloadFile;
FtpWebResponse response = null;
Stream responseStream = null;
MemoryStream downloadCache = null;
try
{
//检索来自服务器的响应，并得到响应流.
response = request.GetResponse() as FtpWebResponse;
this.manager.OnNewMessageArrived(new NewMessageEventArg
{
NewMessage = response.StatusDescription
});
responseStream = response.GetResponseStream();
//内存中的缓存数据.
downloadCache = new MemoryStream(FTPDownloadClient.MaxCacheSize);
byte[] downloadBuffer = new byte[FTPDownloadClient.BufferSize];
int bytesSize = 0;
int cachedSize = 0;
// 下载这个文件直到下载完成.
while (true)
{
//从流中读取数据的缓冲区。
bytesSize = responseStream.Read(downloadBuffer, 0,
downloadBuffer.Length);
//如果这个缓存区是空的，或者下载完成，把在缓存中的数据写到本地文件中。
if (bytesSize == 0 ||
MaxCacheSize < cachedSize + bytesSize)
{
try
{
// 把在缓存中的数据写到本地文件中.
WriteCacheToFile(downloadCache, destPath, cachedSize);
//如果被暂停下载将停止正在下载的文件，取消或者完成.
if (bytesSize == 0)
{
break;
}
// 重置缓存.
downloadCache.Seek(0, SeekOrigin.Begin);
cachedSize = 0;
}
catch (Exception ex)
{
string msg = string.Format(
"There is an error while downloading {0}. "
+ " See InnerException for detailed error. ",
file.Url);
ApplicationException errorException
= new ApplicationException(msg, ex);
//这个错误给了DownloadCompleted事件
ErrorEventArgs e = new ErrorEventArgs
{
ErrorException = errorException
};
this.manager.OnErrorOccurred(e);
return;
}
}
//把缓冲区的数据写到内存中的缓存。
downloadCache.Write(downloadBuffer, 0, bytesSize);
cachedSize += bytesSize;
}
var fileDownloadCompletedEventArgs = new FileDownloadCompletedEventArgs
{
LocalFile = new FileInfo(destPath),
ServerPath = file.Url
};
this.OnFileDownloadCompleted(fileDownloadCompletedEventArgs);
}
finally
{
if (response != null)
{
response.Close();
}
if (responseStream != null)
{
responseStream.Close();
}
if (downloadCache != null)
{
downloadCache.Close();
}
}
}
