选择图像并上传到服务器

我正在编写一个应用程序，其中用户可以上传头像。它似乎工作，，但最后上传的文件/图像在服务器上是空的。我猜图像不会在服务器端正确解码。以下logcat消息:

07-12 16:54:25.809: E/ViewRootImpl(13702): sendUserActionEvent() mView == null
07-12 16:54:26.176: E/JSON(13702): img_xebf47_2014-07-12-16-07-16.jpg
07-12 16:54:26.207: E/JSON Parser(13702): Error parsing data org.json.JSONException: Value img_xebf47_2014-07-12-16-07-16.jpg of type java.lang.String cannot be converted to JSONObject

在Android端我有以下类:

• UploadAvatarActivity.java ->处理相机意图，显示选定的图像，通过调用UserFunctions.java的函数开始上传
• UserFunctions.java ->包含上传头像的函数，函数从UploadAvatarActivity.java获取参数，然后创建JSON对象并解析url和参数
JSONParser.java ->启动http请求

UploadAvatarActivity.java中的相关区域:

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode != RESULT_OK)
            return;
        switch (requestCode) {
        case PICK_FROM_FILE:
            /**
             * After selecting image from files, save the selected path
             */
            mImageCaptureUri = data.getData();
            imagepath = getPath(mImageCaptureUri);
            Bitmap bitmap2 = BitmapFactory.decodeFile(imagepath);
            mImageView.setImageBitmap(bitmap2);
            NetAsync();
            break;
        }
@Override
        protected JSONObject doInBackground(String... args) {
            UserFunctions userFunction = new UserFunctions();
            ByteArrayOutputStream bao = new ByteArrayOutputStream();
            byte[] ba = bao.toByteArray();
            int flag = 0;
            String krt = Base64.encodeToString(ba, flag);
            JSONObject json = userFunction.uploadAvatar(uid, krt);
            return json;
        }

UserFunctions.java:

public class UserFunctions {
    private JSONParser jsonParser;
    // URL of the PHP API
    private static String upload_avatarURL = "http://xxxxxxxx/xxxAPI/";
    // Tag for serverside
    private static String upload_avatar_tag = "uploadavatar";
    // constructor
    public UserFunctions() {
        jsonParser = new JSONParser();
    }

    /**
     * Function to upload avatar
     **/
    public JSONObject uploadAvatar(String uid, String image) {
        // Building Parameters
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("tag", upload_avatar_tag));
        params.add(new BasicNameValuePair("uid", uid));
        params.add(new BasicNameValuePair("image", image));
        JSONObject json = jsonParser.getJSONFromUrl(upload_avatarURL, params);
        return json;
    }
}

这里JASONParser处理http请求:

public class JSONParser {
    static InputStream is = null;
    static JSONObject jObj = null;
    static String json = "";
    // constructor
    public JSONParser() {
    }
    public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) {
        // Making HTTP request
        try {
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setEntity(new UrlEncodedFormEntity(params));
            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "iso-8859-1"), 8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "'n");
            }
            is.close();
            json = sb.toString();
            Log.e("JSON", json);
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.toString());
        }
        // try parse the string to a JSON object
        try {
            jObj = new JSONObject(json);
        } catch (JSONException e) {
            Log.e("JSON Parser", "Error parsing data " + e.toString());
        }
        // return JSON String
        return jObj;
    }
}

最后在服务器端我有以下php代码:

if ($tag == 'uploadavatar') {
        $uid = $_POST['uid'];
        $base = $_POST["image"];

            if (isset($base)) {
            $suffix = $db->createRandomID();
            $image_name = "img_".$suffix."_".date("Y-m-d-H-m-s").".jpg";
            // base64 encoded utf-8 string
            $binary = base64_decode($base);
            // binary, utf-8 bytes
            header("Content-Type: bitmap; charset=utf-8");
            $file = fopen("../images/post_images/" . $image_name, "wb");
            fwrite($file, $binary);
            fclose($file);
            die($image_name);
        } else {
            die("No POST");
        }
 }

如果其他人有同样的问题:

我修改了我的问题:

@Override
        protected JSONObject doInBackground(String... args) {
            UserFunctions userFunction = new UserFunctions();
// Here I had to compress and encode to string!!
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            bitmap2.compress(Bitmap.CompressFormat.JPEG, 100, baos);
            byte[] imageBytes = baos.toByteArray();
            String krt = Base64.encodeToString(imageBytes, Base64.DEFAULT);
            JSONObject json = userFunction.uploadAvatar(uid, krt);
            return json;
        }