可能重复:
How can I programmatically remove the 2 connection limit in WebClient
我的FTP脚本运行良好,直到我开始尝试一次运行多个线程。在过度调试之后,如果另外两个线程已经在做某事,那么FtpWebRequest
只会超时。 (上传,检查文件/目录是否存在或创建目录。)
我已经尝试在ftp类中实现一个锁,这样只有一个线程可以一次创建一个FtpWebRequest
(然后在获得c的响应时关闭锁),但这没有帮助。
每个请求都使用它自己的FtpWebRequest
对象,所以我不太清楚为什么会这样。使用FileZilla
客户端时,我可以将10个文件同时上传到同一个FTP服务器,所以我无法想象它在服务器端是个问题。
.NET中是否有一些静态幕后的东西导致了这个问题?
超时> 2个主题的示例函数:
public class ftp
{
private string host = null;
private string user = null;
private string pass = null;
private int bufferSize = 2048;
/* Construct Object */
public ftp(string hostIP, string userName, string password) { host = hostIP; user = userName; pass = password; }
private object fileFolderCheckLock = new object(); //Only check if a file/dir exists one thread at a time
private object requestLock = new object(); //Don't create multiple ftprequests simultaneously. Exit this lock when the response is being received.
/* Create a New Directory on the FTP Server */
public bool CreateDirectory(string newDirectory)
{
FtpWebRequest ftpRequest = null;
FtpWebResponse ftpResponse = null;
try
{
lock(requestLock)
{
if(!newDirectory.EndsWith("/")) newDirectory += "/";
//Console.WriteLine("chk: "+host + "/" + newDirectory);
Uri theuri = new Uri(host + "/" + newDirectory);
//Console.WriteLine("theuri: "+theuri.ToString());
/* Create an FTP Request */
ftpRequest = (FtpWebRequest)WebRequest.Create(theuri);
/* Log in to the FTP Server with the User Name and Password Provided */
ftpRequest.Credentials = new NetworkCredential(user, pass);
/* When in doubt, use these options */
ftpRequest.UseBinary = true;
ftpRequest.UsePassive = true;
ftpRequest.KeepAlive = true;
ftpRequest.Timeout = 10000;
/* Specify the Type of FTP Request */
ftpRequest.Method = WebRequestMethods.Ftp.MakeDirectory;
/* Establish Return Communication with the FTP Server */
ftpResponse = (FtpWebResponse)ftpRequest.GetResponse();
}
}
catch (Exception ex){ Console.WriteLine("CreateDirectory Exception"+ex.ToString()); }
finally
{
/* Resource Cleanup */
try{ftpResponse.Close();}catch(Exception){}//??
ftpRequest = null;
}
return true;
}
}
有谁能告诉我为什么会这样?
答案 0 :(得分:7)
您可能正在达到默认的最大连接数。看看这个:How can I programmatically remove the 2 connection limit in WebClient