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.'"');

我知道这是一个老帖子，但它仍然非常相关。我发现现代浏览器支持rfc5987，它允许utf-8编码，百分比编码(url编码)。然后Naïve file.txt变成:

Content-Disposition: attachment; filename*=UTF-8''Na%C3%AFve%20file.txt

Safari(5)不支持这一点。相反，你应该使用Safari标准，直接在utf-8编码的头文件中写入文件名:

Content-Disposition: attachment; filename=Naïve file.txt

IE8及以上版本也不支持，你需要使用IE标准的utf-8编码，百分比编码:

Content-Disposition: attachment; filename=Na%C3%AFve%20file.txt

在ASP。Net我使用以下代码:

string contentDisposition;
if (Request.Browser.Browser == "IE" && (Request.Browser.Version == "7.0" || Request.Browser.Version == "8.0"))
    contentDisposition = "attachment; filename=" + Uri.EscapeDataString(fileName);
else if (Request.Browser.Browser == "Safari")
    contentDisposition = "attachment; filename=" + fileName;
else
    contentDisposition = "attachment; filename*=UTF-8''" + Uri.EscapeDataString(fileName);
Response.AddHeader("Content-Disposition", contentDisposition);

我用IE7、IE8、IE9、Chrome 13、Opera 11、FF5、Safari 5测试了上述内容。

2013年11月更新:

这是我目前使用的代码。我仍然必须支持IE8，所以我不能摆脱第一部分。事实证明，Android上的浏览器使用内置的Android下载管理器，它不能可靠地以标准方式解析文件名。

string contentDisposition;
if (Request.Browser.Browser == "IE" && (Request.Browser.Version == "7.0" || Request.Browser.Version == "8.0"))
    contentDisposition = "attachment; filename=" + Uri.EscapeDataString(fileName);
else if (Request.UserAgent != null && Request.UserAgent.ToLowerInvariant().Contains("android")) // android built-in download manager (all browsers on android)
    contentDisposition = "attachment; filename=\"" + MakeAndroidSafeFileName(fileName) + "\"";
else
    contentDisposition = "attachment; filename=\"" + fileName + "\"; filename*=UTF-8''" + Uri.EscapeDataString(fileName);
Response.AddHeader("Content-Disposition", contentDisposition);

上面现在测试在IE7-11, Chrome 32,歌剧12日FF25, Safari 6,使用该文件名下载:你好abcABCæø一ÆØAaouieeiaeiaouyn ½§!#¤%&()=`@£$ € {[]}+´¨^~'-_,;. 三种

在IE7上，它适用于某些字符，但不是所有字符。但是现在谁还关心IE7呢?

这是我用来为Android生成安全文件名的函数。注意，我不知道Android支持哪些字符，但我已经测试过了，这些字符肯定有效:

private static readonly Dictionary<char, char> AndroidAllowedChars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ._-+,@£$€!½§~'=()[]{}0123456789".ToDictionary(c => c);
private string MakeAndroidSafeFileName(string fileName)
{
    char[] newFileName = fileName.ToCharArray();
    for (int i = 0; i < newFileName.Length; i++)
    {
        if (!AndroidAllowedChars.ContainsKey(newFileName[i]))
            newFileName[i] = '_';
    }
    return new string(newFileName);
}

@TomZ:我在IE7和IE8中进行了测试，结果证明我不需要转义撇号(')。你能举个失败的例子吗?

@Dave Van den Eynde:根据RFC6266将两个文件名合并在一行中，除了Android和IE7+8，我已经更新了代码来反映这一点。谢谢你的建议。

@Thilo:不知道GoodReader或其他非浏览器。使用Android方法可能会有一些运气。

@Alex Zhukovskiy:我不知道为什么，但正如在Connect上讨论的那样，它似乎运行得不太好。

我使用以下代码片段进行编码(假设fileName包含文件的文件名和扩展名，即:test.txt):

PHP:

if ( strpos ( $_SERVER [ 'HTTP_USER_AGENT' ], "MSIE" ) > 0 )
{
     header ( 'Content-Disposition: attachment; filename="' . rawurlencode ( $fileName ) . '"' );
}
else
{
     header( 'Content-Disposition: attachment; filename*=UTF-8\'\'' . rawurlencode ( $fileName ) );
}

Java:

fileName = request.getHeader ( "user-agent" ).contains ( "MSIE" ) ? URLEncoder.encode ( fileName, "utf-8") : MimeUtility.encodeWord ( fileName );
response.setHeader ( "Content-disposition", "attachment; filename=\"" + 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.

库类Unicode中的方法mimeHeaderEncode($string)可以完成这项工作。

$file_name= Unicode::mimeHeaderEncode($file_name);

drupal/php中的例子:

https://github.com/drupal/core-utility/blob/8.8.x/Unicode.php

/**
   * Encodes MIME/HTTP headers that contain incorrectly encoded characters.
   *
   * For example, Unicode::mimeHeaderEncode('tést.txt') returns
   * "=?UTF-8?B?dMOpc3QudHh0?=".
   *
   * See http://www.rfc-editor.org/rfc/rfc2047.txt for more information.
   *
   * Notes:
   * - Only encode strings that contain non-ASCII characters.
   * - We progressively cut-off a chunk with self::truncateBytes(). This ensures
   *   each chunk starts and ends on a character boundary.
   * - Using \n as the chunk separator may cause problems on some systems and
   *   may have to be changed to \r\n or \r.
   *
   * @param string $string
   *   The header to encode.
   * @param bool $shorten
   *   If TRUE, only return the first chunk of a multi-chunk encoded string.
   *
   * @return string
   *   The mime-encoded header.
   */
  public static function mimeHeaderEncode($string, $shorten = FALSE) {
    if (preg_match('/[^\x20-\x7E]/', $string)) {
      // floor((75 - strlen("=?UTF-8?B??=")) * 0.75);
      $chunk_size = 47;
      $len = strlen($string);
      $output = '';
      while ($len > 0) {
        $chunk = static::truncateBytes($string, $chunk_size);
        $output .= ' =?UTF-8?B?' . base64_encode($chunk) . "?=\n";
        if ($shorten) {
          break;
        }
        $c = strlen($chunk);
        $string = substr($string, $c);
        $len -= $c;
      }
      return trim($output);
    }
    return $string;
  }

在Content-Disposition中没有可互操作的方法来编码非ascii名称。浏览器兼容性是一团糟。 在Content-Disposition中使用UTF-8的理论上正确的语法是非常奇怪的:filename*=UTF-8 " foo%c3%a4(是的，这是一个星号，没有引号，除了中间的一个空单引号) 这个报头有点不太标准(HTTP/1.1规范承认它的存在，但不要求客户端支持它)。

有一种简单而可靠的替代方法:使用包含所需文件名的URL。

当最后一个斜杠后面的名称是您想要的名称时，您不需要任何额外的头文件!

这个技巧很管用:

/real_script.php/fake_filename.doc

如果你的服务器支持URL重写(例如Apache中的mod_rewrite)，那么你可以完全隐藏脚本部分。

url中的字符应该是UTF-8，逐字节url编码:

/mot%C3%B6rhead   # motörhead