C# 如何让File.Delete（）实际删除我的文件？

我生成一个PDF文件，将其保存在服务器上：

var bytes = ms.ToArray();
. . .
String fileFullpath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory), pdfFileName);
. . .
File.WriteAllBytes(fileFullpath, bytes);

…然后将其保存到Sharepoint文档库中，并将其作为电子邮件附件发送给生成文件的人员：

SavePDFToDocumentLibrary(fileFullpath);
String from = GetFromEmailID();
String to = GetUserEmail();
String subjLine = String.Format("The PDF file you generated ({0})", pdfFileName);
String body = String.Format("The Direct Pay PDF file you generated ({0}) is attached.", pdfFileName);
SendEmailWithAttachment(fileFullpath, from, to, subjLine, body);
// Now that it has been put in a Document Library and emailed, delete the file that was saved locally
File.Delete(fileFullpath);

…此时，我不再需要保存到服务器磁盘上的文件，因此，如上面最后一行所示，尝试将其删除

但是，它不起作用。现在的冗余文件仍在保存位置

为什么？我怎样才能理解“删除”真正的意思是“删除”

更新 以下是Scott希望看到的方法：

// This works; got it from Henry Zucchini's answer at http://stackoverflow.com/questions/468469/how-do-you-upload-a-file-to-a-document-library-in-sharepoint
private void SavePDFToDocumentLibrary(String fullpath)
{
    String fileToUpload = fullpath;
    String sharePointSite = siteUrl;
    String documentLibraryName = "DirectPayPDFForms";

    using (SPSite oSite = new SPSite(sharePointSite))
    {
        using (SPWeb oWeb = oSite.OpenWeb())
        {
            if (!System.IO.File.Exists(fileToUpload))
                throw new FileNotFoundException("File not found.", fileToUpload);

            SPFolder doclib = oWeb.Folders[documentLibraryName];

            // Prepare to upload
            Boolean replaceExistingFiles = true;
            String fileName = System.IO.Path.GetFileName(fileToUpload);
            FileStream fileStream = File.OpenRead(fileToUpload);

            // Upload document
            SPFile spfile = doclib.Files.Add(fileName, fileStream, replaceExistingFiles);

            // Commit 
            doclib.Update();
        }
    }
}

// This is adapted from https://msdn.microsoft.com/en-us/library/system.net.mail.mailmessage(v=vs.90).aspx
public static void SendEmailWithAttachment(string fileToMail, String from, String to, String subj, String body)
{
    String server = GetSMTPHostName(); //"468802-DEV-SPWF"; // change this to prod when go live, or programatically assign?
    // Specify the file to be attached and sent. 
    string file = fileToMail;
    // Create a message and set up the recipients.
    MailMessage message = new MailMessage(
       from,
       to,
       subj,
       body);

    // Create  the file attachment for this e-mail message.
    Attachment data = new Attachment(file, MediaTypeNames.Application.Octet);
    // Add time stamp information for the file.
    ContentDisposition disposition = data.ContentDisposition;
    disposition.CreationDate = System.IO.File.GetCreationTime(file);
    disposition.ModificationDate = System.IO.File.GetLastWriteTime(file);
    disposition.ReadDate = System.IO.File.GetLastAccessTime(file);
    // Add the file attachment to this e-mail message.
    message.Attachments.Add(data);

    //Send the message.
    SmtpClient client = new SmtpClient(server);
    // Add credentials if the SMTP server requires them.
    client.Credentials = CredentialCache.DefaultNetworkCredentials;

    try
    {
        client.Send(message);
    }
    catch (Exception ex)
    {
        Console.WriteLine("Exception caught in CreateMessageWithAttachment(): {0}", ex.ToString());
    }
    // Display the values in the ContentDisposition for the attachment.
    // May not need/want this section
    ContentDisposition cd = data.ContentDisposition;
    Console.WriteLine("Content disposition");
    Console.WriteLine(cd.ToString());
    Console.WriteLine("File {0}", cd.FileName);
    Console.WriteLine("Size {0}", cd.Size);
    Console.WriteLine("Creation {0}", cd.CreationDate);
    Console.WriteLine("Modification {0}", cd.ModificationDate);
    Console.WriteLine("Read {0}", cd.ReadDate);
    Console.WriteLine("Inline {0}", cd.Inline);
    Console.WriteLine("Parameters: {0}", cd.Parameters.Count);
    foreach (DictionaryEntry d in cd.Parameters)
    {
        Console.WriteLine("{0} = {1}", d.Key, d.Value);
    }
    // </ May not need/want this section
    data.Dispose();
}

…IOException捕获块中毕竟存在异常：

进程无法访问文件“C:\Users\TEMP.SP.018\Desktop\DirectPayDynamic\u 2015Jul28\u 19\u 02\u clayshan\u 0.pdf”，因为另一进程正在使用该文件

那么，其他方法中的一种是如何抓住它的呢？ISTM表明SavePDFToDocumentLibrary（）是安全的，因为它使用using块

是data.Dispose（）；在SendEmailWithAttachment（）中不够？我需要在那里显式地调用close，还是什么

更新3

---

我在SendEmailWithAttachment（）中的“data.Dispose（）；”之前添加了“message.Dispose（）；”，但没有任何区别。

尝试处理

SavePDFToDocumentLibrary

中使用的文件流，如下所示：

using (FileStream fileStream = File.OpenRead(fileToUpload))
{
    ...
}

---

您在

SavePDFToDocumentLibrary

或

sendmailwithattachment

中出现错误，该错误未关闭文件。您需要显示这两种方法的代码。具体地说，您使用

fileFullpath

打开文件的位置是根据“如果文件不存在，则不会引发异常”。在删除文件之前，请执行File.Exists（）检查，以查看文件是否由于任何奇怪的原因不存在。您可能还需要处理

SmtpClient

和

MailMessage

（隐式地通过

使用

语句）我以前有过这种情况，不得不求助于重试/睡眠场景——不知何故，文件系统没有立即释放锁。如果你不想正确地点击它们，你可以在特定文件夹中创建文件，并删除该文件夹中超过一分钟的所有文件。。。这两种方法都是丑陋的黑客行为，因为你的代码应该是正确的。@B.ClayShannon在

SavePDFToDocumentLibrary

中使用

文件.OpenRead

怎么样？

using (FileStream fileStream = File.OpenRead(fileToUpload))
{
    ...
}