带有重音符号的MailMessage附件文件名

我正在尝试发送带有附加Excel文件名的HTML电子邮件。 这一切都运行良好，直到我发送其附件名称包含重音字母的消息:-(我尝试过的每一种解决方法都失败了。

原始代码：

var attachment = new Attachment( new MemoryStream(excelFileContents), "simplefilename.xls"); 

这个工作正常。 但是，如果我用“échec.xls”替换“simplefilename.xls”，附件就会被填充（名称和内容）。

我试过这些，但无济于事：

  var attachment = new Attachment( new MemoryStream(excelFileContents), new System.Net.Mime.ContentType("application/vnd.ms-excel")); attachment.Name = "échec.xls"; 

最后一个更糟糕的是： SmtpClient.Send()抛出exception，抱怨文件名中的é ：

  var attachment = new Attachment( new MemoryStream(excelFileContents), new System.Net.Mime.ContentType("application/vnd.ms-excel")); attachment.ContentDisposition.FileName = "échec.xls"; 

我一直在敲打这个太久了。 任何灯都热烈欢迎！

Answer 1

我终于找到了一个有效的答案。

http://social.msdn.microsoft.com/Forums/en-US/dotnetframeworkde/thread/b6c764f7-4697-4394-b45f-128a24306d55

除了Marcel Roma的post外，内容为德语。 我将他的代码放入我的应用程序中。 我能够发出带有重音的pdf，我们看到了附件而不是垃圾。

所以这里是：

 public class AttachmentHelper { public static System.Net.Mail.Attachment CreateAttachment(string attachmentFile, string displayName, TransferEncoding transferEncoding) { System.Net.Mail.Attachment attachment = new System.Net.Mail.Attachment(attachmentFile); attachment.TransferEncoding = transferEncoding; string tranferEncodingMarker = String.Empty; string encodingMarker = String.Empty; int maxChunkLength = 0; switch (transferEncoding) { case TransferEncoding.Base64: tranferEncodingMarker = "B"; encodingMarker = "UTF-8"; maxChunkLength = 30; break; case TransferEncoding.QuotedPrintable: tranferEncodingMarker = "Q"; encodingMarker = "ISO-8859-1"; maxChunkLength = 76; break; default: throw (new ArgumentException(String.Format("The specified TransferEncoding is not supported: {0}", transferEncoding, "transferEncoding"))); } attachment.NameEncoding = Encoding.GetEncoding(encodingMarker); string encodingtoken = String.Format("=?{0}?{1}?", encodingMarker, tranferEncodingMarker); string softbreak = "?="; string encodedAttachmentName = encodingtoken; if (attachment.TransferEncoding == TransferEncoding.QuotedPrintable) encodedAttachmentName = HttpUtility.UrlEncode(displayName, Encoding.Default).Replace("+", " ").Replace("%", "="); else encodedAttachmentName = System.Convert.ToBase64String(Encoding.UTF8.GetBytes(displayName)); encodedAttachmentName = SplitEncodedAttachmentName(encodingtoken, softbreak, maxChunkLength, encodedAttachmentName); attachment.Name = encodedAttachmentName; return attachment; } private static string SplitEncodedAttachmentName(string encodingtoken, string softbreak, int maxChunkLength, string encoded) { int splitLength = maxChunkLength - encodingtoken.Length - (softbreak.Length * 2); var parts = SplitByLength(encoded, splitLength); string encodedAttachmentName = encodingtoken; foreach (var part in parts) encodedAttachmentName += part + softbreak + encodingtoken; encodedAttachmentName = encodedAttachmentName.Remove(encodedAttachmentName.Length - encodingtoken.Length, encodingtoken.Length); return encodedAttachmentName; } private static IEnumerable SplitByLength(string stringToSplit, int length) { while (stringToSplit.Length > length) { yield return stringToSplit.Substring(0, length); stringToSplit = stringToSplit.Substring(length); } if (stringToSplit.Length > 0) yield return stringToSplit; } } 

以下列方式使用它：

 static void Main(string[] args) { string smtpServer = String.Empty; string userName = String.Empty; string password = String.Empty; string attachmentFilePath = String.Empty; string displayName = String.Empty; System.Net.Mail.SmtpClient client = new System.Net.Mail.SmtpClient(smtpServer); client.Credentials = new System.Net.NetworkCredential(userName, password); var msg = new System.Net.Mail.MailMessage(fromAddress, toAddress, "Subject", "Body"); System.Net.Mail.Attachment attachment = AttachmentHelper.CreateAttachment(attachmentFilePath, displayName, TransferEncoding.Base64); msg.Attachments.Add(attachment); client.Send(msg); } 

Answer 2

您需要使用Quoted-Printable格式作为附件名称：

• C＃：用于解码Quoted-Printable编码的类？
• http://www.codeproject.com/KB/security/TextCoDec.aspx