Question

我目前有一个.NET http处理程序，用于处理将文件传递到Web浏览器以供下载。 IE6 +，FireFox，Chrome和Safari都使用此代码，但新的IE9无法下载，但仅限于SSL。

当我点击链接下载文件时： https://rootwebsite/taskmanager/DownloadFiles.ashx?fileId=3b2c7e41-f51a-445d-9627-f4f4481e1425

IE9打开保存对话框并显示DownloadFiles_ashx?fileId=3b2c7e41-f51a-445d-9627-f4f4481e1425作为文件名，但拒绝下载文件。

如果我将链接更改为http://，则代码正常，文件将下载。

区别是什么？我错过了什么？

这是我的代码：

public void WriteByteArrayToHttp(HttpResponse response, string fileName, string contentType, Stream file, bool downloadFile)
{
    using (file)
    {
        if (downloadFile)
        {
            response.Clear();
            response.ClearHeaders();
            response.ClearContent();
            response.AddHeader("Content-Disposition",
                               string.Format("attachment; filename={0}", HttpUtility.UrlEncode(fileName)));
        }
        response.AddHeader("Content-Length", file.Length.ToString());

        // Added with suggestion of YSlow FireFox plug-in
        // Specifies how long the file is valid for in cache in seconds
        // http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
        // See 14.9 Cache-Control
        // 6 Hours
        response.AddHeader("max-age", "21600");
        response.ContentType = contentType;

        // At the time of this writing, we are running IIS6, BUT if we decide to go to IIS7
        // there is a 28.6MB limit to content size both up and down by default
        // See http://msdn.microsoft.com/en-us/library/ms689462.aspx
        // This would be a problem for a number of files we serv up with the Original method
        // so this chunking method replaces that.
        // See http://support.microsoft.com/kb/812406 as the base for this change.
        // Tested with file between 1MB and 3GB

        // Total bytes to read:
        long dataToRead = file.Length;

        // Buffer to read 10K bytes in chunk:
        byte[] buffer = new Byte[10000];

        try
        {
            while (dataToRead > 0)
            {
                // Verify that the client is connected.
                if (response.IsClientConnected)
                {
                    // Read the data in buffer.
                    // Length of the file:
                    int length = file.Read(buffer, 0, 10000);

                    // Write the data to the current output stream.
                    response.OutputStream.Write(buffer, 0, length);

                    // Flush the data to the HTML output.
                    response.Flush();

                    buffer = new Byte[10000];
                    dataToRead = dataToRead - length;
                }
                else
                {
                    //prevent infinite loop if user disconnects
                    dataToRead = -1;
                }
            }
        }
        catch (HttpException hex)
        {
            if (!hex.Message.StartsWith("The remote host closed the connection"))
            {
                throw;
            }
        }
    }
}

web.config将处理程序定义为：

 <system.webServer>
    <validation validateIntegratedModeConfiguration="false"/>
    <handlers>
      <add name="DownloadFiles.ashx" path="DownloadFiles.ashx" verb="*" type="Russound.Web.HttpHandlers.DownloadFileHandler" resourceType="Unspecified" preCondition="integratedMode"/>
    </handlers>
  </system.webServer>
</configuration>

Answer 1

可能与

有关

部分cache control headers（或this one;另见question）或
一个Internet Explorer选项，可防止SSL加密的页面缓存/存储在磁盘上，或
他们两个......

昨天让我头疼（这是我的第二个）。

如果你问我，这个Internet Explorer选项Do not save encrypted pages to disk应该只适用于缓存而不是故意下载......但是，嘿，这是微软我们正在谈论的，所以它不需要无论如何都要有任何意义。

见这里：http://blogs.msdn.com/b/ieinternals/archive/2009/10/03/internet-explorer-cannot-download-over-https-when-no-cache.aspx：

2011年2月更新：我修改了 IE9的文件下载逻辑。 IE9 应该能够成功无论HTTPS还是HTTPS，都可以下载文件除非你有，否则Cache-Control标头 “不要将加密的页面保存到磁盘“选项集。

在SSL期间下载IE9中的文件行为更改

1 个答案: