在asp.net mvc2中，我使用这样的东西:

return File(
    tempFile
    , "application/octet-stream"
    , HttpUtility.UrlPathEncode(fileName)
    );

我想如果你不使用mvc(2)，你可以只编码文件名使用

HttpUtility.UrlPathEncode(fileName)

只是一个更新，因为我今天为了回应一个客户的问题而尝试了所有这些东西

With the exception of Safari configured for Japanese, all browsers our customer tested worked best with filename=text.pdf - where text is a customer value serialized by ASP.Net/IIS in utf-8 without url encoding. For some reason, Safari configured for English would accept and properly save a file with utf-8 Japanese name but that same browser configured for Japanese would save the file with the utf-8 chars uninterpreted. All other browsers tested seemed to work best/fine (regardless of language configuration) with the filename utf-8 encoded without url encoding. I could not find a single browser implementing Rfc5987/8187 at all. I tested with the latest Chrome, Firefox builds plus IE 11 and Edge. I tried setting the header with just filename*=utf-8''texturlencoded.pdf, setting it with both filename=text.pdf; filename*=utf-8''texturlencoded.pdf. Not one feature of Rfc5987/8187 appeared to be getting processed correctly in any of the above.

在。net 4.5(和Core 1.0)中，你可以使用ContentDispositionHeaderValue来为你格式化。

var fileName = "Naïve file.txt";
var h = new System.Net.Http.Headers.ContentDispositionHeaderValue("attachment");
h.FileNameStar = fileName;
h.FileName = "fallback-ascii-name.txt";

Response.Headers.Add("Content-Disposition", h.ToString());

h.ToString()将导致:

attachment; filename*=utf-8''Na%C3%AFve%20file.txt; filename=fallback-ascii-name.txt

我在所有主流浏览器中测试了以下代码，包括老式的explorer(通过兼容模式)，它在任何地方都能正常工作:

$filename = $_GET['file']; //this string from $_GET is already decoded
if (strstr($_SERVER['HTTP_USER_AGENT'],"MSIE"))
  $filename = rawurlencode($filename);
header('Content-Disposition: attachment; filename="'.$filename.'"');

以下文件链接自Jim在回答中提到的RFC草案，进一步解决了这个问题，在这里值得直接注意:

HTTP内容处理头和rfc2231 /2047编码的测试用例

在提议的RFC 5987“超文本传输协议(HTTP)报头字段参数的字符集和语言编码”中对此进行了讨论，包括浏览器测试和向后兼容性的链接。

RFC 2183表示这样的报头应该根据RFC 2184进行编码，RFC 2184已被RFC 2231废止，上面的RFC草案涵盖了这一点。