http上下文响应C#中的文件块下载

Question

我有一个下面的场景。

客户端向服务器-1发送文件下载请求服务器-1向服务器-2发送文件请求。

为了实现这一点，我需要创建一种机制，一旦客户端向Server-1发送请求，Server-1就会向Server-2发送请求，后者会将文件作为响应输出流分块发送。服务器-1将不断地向客户端浏览器发送这个文件块，因为它不断地从服务器-2接收。

我已经完成了如下代码，理论上它看起来很好，但仍然不起作用。它没有在客户端浏览器中下载整个文件，似乎最后一个块没有传输到Server-1，或者它没有从Server-1 下载到客户端浏览器

服务器-1代码(当客户端请求下载文件时(

private void ProccesBufferedResponse(HttpWebRequest webRequest, HttpContext context)
{
char[] responseChars = null;
byte[] buffer = null;
if (webRequest == null)
logger.Error("Request string is null for Perfios Docs Download at ProccesBufferedResponse()");
context.Response.Buffer = false;
context.Response.BufferOutput = false;
try
{
WebResponse webResponse = webRequest.GetResponse();
context.Response.ContentType = "application/pdf";
context.Response.AddHeader("Content-disposition", webResponse.Headers["Content-disposition"]);
StreamReader responseStream = new StreamReader(webResponse.GetResponseStream());
while (!responseStream.EndOfStream)
{
responseChars = new char[responseStream.ToString().ToCharArray().Length];
responseStream.Read(responseChars, 0, responseChars.Length);
buffer = Encoding.ASCII.GetBytes(responseChars);
context.Response.Clear();
context.Response.OutputStream.Write(buffer, 0, buffer.Length);
context.Response.Flush();
}
}
catch (Exception ex)
{
throw;
}
finally
{
context.Response.Flush();
context.Response.End();
}
}

服务器-2代码(其中服务器-1将发送文件请求(

private void DownloadInstaPerfiosDoc(int CompanyID, string fileName, string Foldertype)
{
string folderPath;
string FilePath;
int chunkSize = 1024;
int startIndex = 0;
int endIndex = 0;
int length = 0;
byte[] bytes = null;
DirectoryInfo dir;
folderPath = GetDocumentDirectory(CompanyID, Foldertype);
FilePath = folderPath + "\" + fileName;
dir = new DirectoryInfo(folderPath);
HttpContext.Current.Response.Buffer = false;
HttpContext.Current.Response.BufferOutput = false;
if (dir.Exists && dir.GetFiles().Length > 0)
{
foreach (var file in dir.GetFiles(fileName))
{
FilePath = folderPath + "\" + file.Name;
FileStream fsReader = new FileStream(FilePath, FileMode.Open, FileAccess.Read);
HttpContext.Current.Response.ContentType = "application/pdf";
HttpContext.Current.Response.AddHeader("Content-disposition", string.Format("attachment; filename = "{0}"", fileName));
int totalChunks = (int)Math.Ceiling((double)fsReader.Length / chunkSize);
for (int i = 0; i < totalChunks; i++)
{
startIndex = i * chunkSize;
if (startIndex + chunkSize > fsReader.Length)
endIndex = (int)fsReader.Length;
else
endIndex = startIndex + chunkSize;
length = (int)endIndex - startIndex;
bytes = new byte[length];
fsReader.Read(bytes, 0, bytes.Length);
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.OutputStream.Write(bytes, 0, bytes.Length);
HttpContext.Current.Response.Flush();
}
}
}
}

请帮我解决这个问题。

Answer 1

这是可能的，也是可行的。我会给你一个伪程序，让你理解整个想法。

服务器1

download action gets hit
create a request to server2
get the response stream of your server2 request
read the response stream in desired chunk sizes until it's consumed completely
write each chunk (as soon as you read) to current response stream

服务器2

download action gets hit
write your stream onto your current response stream however you like