我有这样的场景
while ( until toUpload list empty)
{
create ftp folder (list.item);
if (upload using ftp (list.item.fileName))
{
update Uploaded list that successfully updated;
}
}
update database using Uploaded list;
这里我使用同步方法在这个循环中上传文件。我有一个要求优化这个上传。我发现这篇文章如何提高 FtpWebRequest 的性能?并按照他们提供的说明进行操作。因此我达到了 2000 秒到 1000 秒的时间。然后我开始使用异步上传,如 msdn 中的此示例所示。http://msdn.microsoft.com/en-us/library/system.net.ftpwebrequest(v=vs.90).aspx。我改变了方法
if (upload using ftp (list.item.fileName))
至
if (aync upload using ftp (list.item.fileName))
但事情变得更糟了。时间变成1000s到4000s。
我必须将许多文件上传到我的 ftp 服务器。因此最好的方法应该是(猜测)异步的。有人帮助我如何以正确的方式做到这一点。我无法找到如何正确使用上面的 msdn 示例代码。
我的代码 - 同步(删除异常处理以节省空间):
public bool UploadFtpFile(string folderName, string fileName)
{
try
{
string absoluteFileName = Path.GetFileName(fileName);
var request = WebRequest.Create(new Uri(
String.Format(@"ftp://{0}/{1}/{2}",
this.FtpServer, folderName, absoluteFileName))) as FtpWebRequest;
request.Method = WebRequestMethods.Ftp.UploadFile;
request.UseBinary = true;
request.UsePassive = true;
request.KeepAlive = true;
request.Credentials = this.GetCredentials();
request.ConnectionGroupName = this.ConnectionGroupName;
request.ServicePoint.ConnectionLimit = 8;
using (FileStream fs = File.OpenRead(fileName))
{
byte[] buffer = new byte[fs.Length];
fs.Read(buffer, 0, buffer.Length);
fs.Close();
using(var requestStream = request.GetRequestStream())
{
requestStream.Write(buffer, 0, buffer.Length);
}
}
using (var response = (FtpWebResponse)request.GetResponse())
{
return true;
}
}
catch // real code catches correct exceptions
{
return false;
}
}
异步方法
public bool UploadFtpFile(string folderName, string fileName)
{
try
{
//this methods is exact method provide in msdn example mail method
AsyncUploadFtp(String.Format(@"ftp://{0}/{1}/{2}",
this.FtpServer, folderName, Path.GetFileName(fileName)), fileName);
return true;
}
catch // real code catches correct exceptions
{
return false;
}
}