private void CloseDataConn()
{
if (dataConn != null)
{
//如果当前的dataConn还在处于等待连接或者发送数据状态，就取消这些操作
dataConn.AsyncHelper.CancelAsyncOperation();
dataConn.Stop();
dataConn = null;
}
}
void CreateDataConnection()
{
//关闭以前的数据连接
CloseDataConn();
//生成新的数据连接
dataConn = new FtpDataConnection();
dataConn.Start();
IPEndPoint localPoint = (IPEndPoint)dataConn.Socket.LocalEndPoint;
string ipAddress = ftpServer.PasvIPSetting.Replace(".", ",");
StringBuilder reply = new StringBuilder();
reply.Append("227 Entering Passive Mode(");
reply.Append(ipAddress);
reply.Append(",");
reply.Append(localPoint.Port / 256);
reply.Append(",");
reply.Append(localPoint.Port % 256);
reply.Append(").");
Response(reply.ToString());
try
{
//在规定时间内等待客户端的数据连接
dataConn.Accept(opertionTimeout);
}
catch (TimeoutException)
{
CloseDataConn();
NetDebuger.PrintDebugMessage("Timeout wait for data connection");
}
catch
{
CloseDataConn();
NetDebuger.PrintDebugMessage("Interrupted for wait for data connection");
}
}