Android使用post方式上传图片到服务器的方法

本文实例讲述了Android使用post方式上传图片到服务器的方法。分享给大家供大家参考，具体如下：

/**
 * 上传文件到服务器类
 *
 * @author tom
 */
public class UploadUtil {
  private static final String TAG = "uploadFile";
  private static final int TIME_OUT = 10 * 1000; // 超时时间
  private static final String CHARSET = "utf-8"; // 设置编码
  /**
   * Android上传文件到服务端
   *
   * @param file 需要上传的文件
   * @param RequestURL 请求的rul
   * @return 返回响应的内容
   */
  public static String uploadFile(File file, String RequestURL) {
    String result = null;
    String BOUNDARY = UUID.randomUUID().toString(); // 边界标识 随机生成
    String PREFIX = "--", LINE_END = "\r\n";
    String CONTENT_TYPE = "multipart/form-data"; // 内容类型
    try {
      URL url = new URL(RequestURL);
      HttpURLConnection conn = (HttpURLConnection) url.openConnection();
      conn.setReadTimeout(TIME_OUT);
      conn.setConnectTimeout(TIME_OUT);
      conn.setDoInput(true); // 允许输入流
      conn.setDoOutput(true); // 允许输出流
      conn.setUseCaches(false); // 不允许使用缓存
      conn.setRequestMethod("POST"); // 请求方式
      conn.setRequestProperty("Charset", CHARSET); // 设置编码
      conn.setRequestProperty("connection", "keep-alive");
      conn.setRequestProperty("Content-Type", CONTENT_TYPE + ";boundary=" + BOUNDARY);
      if (file != null) {
        /**
         * 当文件不为空，把文件包装并且上传
         */
        DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
        StringBuffer sb = new StringBuffer();
        sb.append(PREFIX);
        sb.append(BOUNDARY);
        sb.append(LINE_END);
        /**
         * 这里重点注意： name里面的值为服务端需要key 只有这个key 才可以得到对应的文件
         * filename是文件的名字，包含后缀名的 比如:abc.png
         */
        sb.append("Content-Disposition: form-data; name=\"uploadfile\"; filename=\""
            + file.getName() + "\"" + LINE_END);
        sb.append("Content-Type: application/octet-stream; charset=" + CHARSET + LINE_END);
        sb.append(LINE_END);
        dos.write(sb.toString().getBytes());
        InputStream is = new FileInputStream(file);
        byte[] bytes = new byte[1024];
        int len = 0;
        while ((len = is.read(bytes)) != -1) {
          dos.write(bytes, 0, len);
        }
        is.close();
        dos.write(LINE_END.getBytes());
        byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINE_END).getBytes();
        dos.write(end_data);
        dos.flush();
        /**
         * 获取响应码 200=成功 当响应成功，获取响应的流
         */
        int res = conn.getResponseCode();
        Log.e(TAG, "response code:" + res);
        // if(res==200)
        // {
        Log.e(TAG, "request success");
        InputStream input = conn.getInputStream();
        StringBuffer sb1 = new StringBuffer();
        int ss;
        while ((ss = input.read()) != -1) {
          sb1.append((char) ss);
        }
        result = sb1.toString();
        Log.e(TAG, "result : " + result);
        // }
        // else{
        // Log.e(TAG, "request error");
        // }
      }
    } catch (MalformedURLException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
    return result;
  }
  /**
   * 通过拼接的方式构造请求内容，实现参数传输以及文件传输
   *
   * @param url Service net address
   * @param params text content
   * @param files pictures
   * @return String result of Service response
   * @throws IOException
   */
  public static String post(String url, Map<String, String> params, Map<String, File> files)
      throws IOException {
    String BOUNDARY = java.util.UUID.randomUUID().toString();
    String PREFIX = "--", LINEND = "\r\n";
    String MULTIPART_FROM_DATA = "multipart/form-data";
    String CHARSET = "UTF-8";
    URL uri = new URL(url);
    HttpURLConnection conn = (HttpURLConnection) uri.openConnection();
    conn.setReadTimeout(10 * 1000); // 缓存的最长时间
    conn.setDoInput(true);// 允许输入
    conn.setDoOutput(true);// 允许输出
    conn.setUseCaches(false); // 不允许使用缓存
    conn.setRequestMethod("POST");
    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=\"uploadfile\"; filename=\""
            + file.getValue().getName() + "\"" + 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();
    // 得到响应码
    int res = conn.getResponseCode();
    InputStream in = conn.getInputStream();
    StringBuilder sb2 = new StringBuilder();
    if (res == 200) {
      int ch;
      while ((ch = in.read()) != -1) {
        sb2.append((char) ch);
      }
    }
    outStream.close();
    conn.disconnect();
    return sb2.toString();
  }
}

示例调用第二种方式上传：

final Map<String, String> params = new HashMap<String, String>();
params.put("send_userId", String.valueOf(id));
params.put("send_email", address);
params.put("send_name", name);
params.put("receive_email", emails);
final Map<String, File> files = new HashMap<String, File>();
files.put("uploadfile", file);
final String request = UploadUtil.post(requestURL, params, files);

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希望本文所述对大家Android程序设计有所帮助。