java - 使用 HttpURLConnection 发送 MultipartEntity

Question

使用下面的代码，我可以将一个大文件发送到服务器，但我似乎无法找到如何发送带有文件的文本。(发送文件加上额外的数据(用户名，密码..)例子)。并在服务器端接收它。

FileInputStream fileInputStream = new FileInputStream(new File(
                   pathToOurFile));
URL url = new URL(urlServer);
            connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
           connection.setDoOutput(true);
            connection.setUseCaches(false);
            connection.setChunkedStreamingMode(1024);
            // Enable POST method
            connection.setRequestMethod("POST");

            connection.setRequestProperty("Connection", "Keep-Alive");
            connection.setRequestProperty("Content-Type",
                    "multipart/form-data;boundary=" + boundary);

            outputStream = new DataOutputStream(connection.getOutputStream());
            outputStream.writeBytes(twoHyphens + boundary + lineEnd);
 String connstr = null;

            connstr = "Content-Disposition: form-data; name=\"uploadedVideos\";filename=\""
                    + pathToOurFile + "\"" + lineEnd;
outputStream.writeBytes(connstr);
outputStream.writeBytes(lineEnd);
bytesAvailable = fileInputStream.available();
            bufferSize = Math.min(bytesAvailable, maxBufferSize);
            buffer = new byte[bufferSize];

            // Read file
            bytesRead = fileInputStream.read(buffer, 0, bufferSize);
try {
               while (bytesRead > 0) {
                    try {
                        outputStream.write(buffer, 0, bufferSize);
                    } catch (OutOfMemoryError e) {
                        e.printStackTrace();
                        response = "outofmemoryerror";
                        return response;
                    }
                    bytesAvailable = fileInputStream.available();
                    bufferSize = Math.min(bytesAvailable, maxBufferSize);
                    bytesRead = fileInputStream.read(buffer, 0, bufferSize);
                }
            } catch (Exception e) {
                e.printStackTrace();
                response = "error";
                return response;
            }
            outputStream.writeBytes(lineEnd);
            outputStream.writeBytes(twoHyphens + boundary + twoHyphens
                    + lineEnd);
       fileInputStream.close();
        outputStream.flush();
        outputStream.close();

服务器部分:

HttpPostedFile file = HttpContext.Current.Request.Files[0];
string fname = Path.GetFileName(file.FileName);
   file.SaveAs(Server.MapPath(Path.Combine("~/UploadedVideos/" + Date  + "/", fname)));

如有任何帮助，我们将不胜感激。我知道我可以使用 HttpClient 来做到这一点，但它在大文件的情况下对我不起作用，所以我想使用这种方式。

Answer 1

使用这个，

  private static String multipost(String urlString, MultipartEntity reqEntity) {

        try {
            URL url = new URL(urlString);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setReadTimeout(10000);
            conn.setConnectTimeout(15000);
            conn.setRequestMethod("POST");
            conn.setUseCaches(false);
            conn.setDoInput(true);
            conn.setDoOutput(true);

            conn.setRequestProperty("Connection", "Keep-Alive");
            conn.addRequestProperty("Content-length", reqEntity.getContentLength()+"");
            conn.addRequestProperty(reqEntity.getContentType().getName(), reqEntity.getContentType().getValue());

            OutputStream os = conn.getOutputStream();
            reqEntity.writeTo(conn.getOutputStream());
            os.close();
            conn.connect();

            if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
                return readStream(conn.getInputStream());
            }

        } catch (Exception e) {
            Log.e("MainActivity", "multipart post error " + e + "(" + urlString + ")");
        }
        return null;
    }

    private static String readStream(InputStream in) {
        BufferedReader reader = null;
        StringBuilder builder = new StringBuilder();
        try {
            reader = new BufferedReader(new InputStreamReader(in));
            String line = "";
            while ((line = reader.readLine()) != null) {
                builder.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return builder.toString();
    }

在这里您可以使用 MultipartEntiry 如下所示设置文件、用户名和密码。

 private void uploadMultipartData() throws UnsupportedEncodingException {

        MultipartEntity reqEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
        reqEntity.addPart("fileToUpload", new FileBody(uploadFile));
        reqEntity.addPart("uname", new StringBody("MyUserName"));
        reqEntity.addPart("pwd", new StringBody("MyPassword"));
        String response = multipost(server_url, reqEntity);

        Log.d("MainActivity", "Response :"+response);
    }

注意:您需要添加httpmime jar 在你的 libs 文件夹中。