ASP MVC 通过从 sftp 读取将文件返回给浏览器

Question

我能够从 sftp 获取文件流，但无法从控制器的浏览器 (chrome) ui 中呈现该文件流。

如果我将文件存储在磁盘中，然后返回它的工作正常，但我想通过直接返回流而不是存储任何文件来做到这一点

下面是我的代码

public ActionResult View(字符串路径) {

        string contentType = "";

        var filePath = Server.MapPath(path);

        switch (System.IO.Path.GetExtension(filePath).ToLower())
        {
            case ".htm":
            case ".html":
                contentType = "text/HTML";
                break;

            case ".txt":
                contentType = "text/plain";
                break;

            case ".doc":
            case ".rtf":
            case ".docx":
                contentType = "Application/msword";
                break;

            case ".xls":
            case ".xlsx":
                contentType = "Application/x-msexcel";
                break;

            case ".jpg":
            case ".jpeg":
                contentType = "image/jpeg";
                break;

            case ".gif":
                contentType = "image/GIF";
                break;

            case ".png":
                contentType = "image/png";
                break;

            //case ".bmp":
            //    contentType = "image/x-ms-bmp";
            //    break;

            case ".pdf":
                contentType = "application/pdf";
                break;
            case ".bmp":
                contentType = "image/bmp";
                break;
        }

        try
        {

            Stream file = null;

            SftpClient conn = null;


            if (contentType != "")
            {
                conn = GetSFTPConnection();

                conn.Connect();

                file = new MemoryStream();

                if (conn.Exists(path))
                {
                    conn.DownloadFile(path, file);
                }
                else
                {
                    throw new SftpPathNotFoundException();
                }

                return File(file, contentType);

            }
        }
        catch (Exception)
        {

            throw new Exception("Unable To Get Requested File");
        }
        return null;
    }

Answer 1

我没有对此进行测试，但我认为您需要将文件发送到响应中，例如替换：

return File(file, contentType);

与：

var response = HttpContext.Current.Response;
response.BufferOutput = false;
response.OutputStream.Write(file, 0, file.Length);
response.Flush();
response.End();

并且可能会更改您的操作以返回 FileResult 而不是 ActionResult。