Question

我有以下代码：

try
{
    context.Response.TransmitFile(savedFileName);
}
catch (Exception ex)
{
    ExceptionUtility.LogException(new Exception("Exception while transmit zip [AttachmentsSecurityHandler.cs]: " + ex.Message), false);
}
finally
{
    try
    {
        Thread.Sleep(500);
        File.Delete(savedFileName);
    }
    catch (Exception ex)
    {
        ExceptionUtility.LogException(new Exception("Unable to delete temp zip file [AttachmentsSecurityHandler.cs]: " + ex.Message), false);
    }
}

一切正常，只有当用户取消下载时我才会得到：

Exception while transmit zip [AttachmentsSecurityHandler.cs]: The remote host closed the connection. The error code is 0x800703E3.
Unable to delete temp zip file [AttachmentsSecurityHandler.cs]: The process cannot access the file 'D:\Hosting\***\html\attachments\tempCompressed\b9b5c47e-86f9-4610-9293-3b92dbaee222' because it is being used by another process.

删除孤立文件的唯一方法是尝试删除旧的（例如小时）文件？系统将保持多长时间锁定（GoDaddy共享主机）？谢谢。

Answer 1

1）我认为您应该在TransmitFile（）之后放置context.Response.Flush（），以确保在继续删除文件之前将文件流式传输到客户端。

2）TransferFile（）也流式传输文件而不在内存中缓冲它。这将在文件正在使用时锁定该文件。您可能希望将其加载到内存并使用Response.OutputStream。

Answer 2

我已经从GoDaddy转移到Arvixe（原因：发送电子邮件时遇到很大问题），更改了代码，直到现在一切正常（成功和中断下载）：

try
{
    context.Response.TransmitFile(savedFileName);
}
catch (Exception ex)
{
    ExceptionUtility.LogException(new Exception("Exception while transmit zip [AttachmentsSecurityHandler.cs]: " + ex.Message), false);
}
finally
{
    byte attemptsCounter = 0;

    Thread deletingThread = new Thread(delegate()
      {
          while (attemptsCounter < 5)
          {
              Thread.Sleep(5000);
              try
              {
                  File.Delete(savedFileName);
                  break;
              }
              catch (Exception ex)
              {
                  attemptsCounter++;
                  ExceptionUtility.LogException(new Exception(string.Format("Unable to delete temp zip file [AttachmentsSecurityHandler.cs] (attempt {0}): {1}", attemptsCounter, ex.Message)), false);
               }
          }
      });

    deletingThread.Start();
}

ASP.NET在TransmitFile中的异常后删除文件

2 个答案: