Android实现多参数文件和数据上传

/**
 * 可传入多张图片和参数
 * 
 * @param actionUrl
 *   发送地址
 * @param params
 *   文本参数
 * @param files
 *   文件参数
 * @return
 * @throws IOException
 */
 public static String mulpost(String actionUrl, Map<String, String> params,
 Map<String, File> files) throws IOException {
 String result = "";
 
 String BOUNDARY = java.util.UUID.randomUUID().toString();
 String PREFIX = "--", LINEND = "rn";
 String MULTIPART_FROM_DATA = "multipart/form-data";
 String CHARSET = "UTF-8";
 URL uri = new URL(actionUrl);
 HttpURLConnection conn = (HttpURLConnection) uri.openConnection();
 conn.setReadTimeout(5 * 1000);
 conn.setDoInput(true);// 允许输入
 conn.setDoOutput(true);// 允许输出
 conn.setUseCaches(false);
 conn.setRequestMethod("POST"); // Post方式
 conn.setRequestProperty("connection", "keep-alive");
 conn.setRequestProperty("Charsert", "UTF-8");
 conn.setRequestProperty("Content-Type", MULTIPART_FROM_DATA
 + ";boundary=" + BOUNDARY);
 
 // 首先组拼文本类型的参数
 StringBuilder sb = new StringBuilder();
 for (Map.Entry<String, String> entry : params.entrySet()) {
 sb.append(PREFIX);
 sb.append(BOUNDARY);
 sb.append(LINEND);
 sb.append("Content-Disposition: form-data; name=""
  + entry.getKey() + """ + LINEND);
 sb.append("Content-Type: text/plain; charset=" + CHARSET + LINEND);
 sb.append("Content-Transfer-Encoding: 8bit" + LINEND);
 sb.append(LINEND);
 sb.append(entry.getValue());
 sb.append(LINEND);
 }
 
 DataOutputStream outStream = new DataOutputStream(
 conn.getOutputStream());
 outStream.write(sb.toString().getBytes());
 
 // 发送文件数据
 if (files != null)
 for (Map.Entry<String, File> file : files.entrySet()) {
 StringBuilder sb1 = new StringBuilder();
 sb1.append(PREFIX);
 sb1.append(BOUNDARY);
 sb1.append(LINEND);
 sb1.append("Content-Disposition: form-data; name="file"; filename=""
  + file.getKey() + """ + LINEND);
 sb1.append("Content-Type: application/octet-stream; charset="
  + CHARSET + LINEND);
 sb1.append(LINEND);
 outStream.write(sb1.toString().getBytes());
 InputStream is = new FileInputStream(file.getValue());
 byte[] buffer = new byte[1024];
 int len = 0;
 while ((len = is.read(buffer)) != -1) {
  outStream.write(buffer, 0, len);
 }
 
 is.close();
 outStream.write(LINEND.getBytes());
 }
 
 // 请求结束标志
 byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINEND).getBytes();
 outStream.write(end_data);
 outStream.flush();
 
 InputStream is = conn.getInputStream();
 InputStreamReader isr = new InputStreamReader(is, "utf-8");
 BufferedReader br = new BufferedReader(isr);
 result = br.readLine();
 outStream.close();
 conn.disconnect();
 return result;
 }

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />