使用 HttpUrlConnection Android 將 base64 編碼的圖像發送到服務器

Question

我正在嘗試使用 HttpUrlConnection 將 base64 編碼的圖像發送到服務器。 我遇到的問題是大多數圖像都已成功發送，但有些會生成 FileNotFound 異常。 我用於編碼圖像的代碼可以在下面找到。

public static String encodeImage(Bitmap thumbnail) {
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            thumbnail.compress(Bitmap.CompressFormat.JPEG, 100, baos);
            byte[] b = baos.toByteArray();
            String imageEncoded = Base64.encodeToString(b,Base64.URL_SAFE);
            return imageEncoded;
        }

當我更改線路時：

String imageEncoded = Base64.encodeToString(b,Base64.URL_SAFE);

到：

String imageEncoded = Base64.encodeToString(b,Base64.DEFAULT);

然后大多數圖像生成 FileNotFoundException 並且一些被成功發送到服務器。

下面是我的 HttpUrlConnection 的代碼：

public class HttpManager {

    public static String getData(RequestPackage p) {

        BufferedReader reader = null;
        String uri = p.getUri();
        if (p.getMethod().equals("GET")) {
            uri += "?" + p.getEncodedParams();
        }

        try {
            URL url = new URL(uri);
            HttpURLConnection con = (HttpURLConnection) url.openConnection();
            con.setRequestMethod(p.getMethod());


            if (p.getMethod().equals("POST")) {
                con.setDoOutput(true);
                OutputStreamWriter writer = new OutputStreamWriter(con.getOutputStream());
                writer.write(p.getEncodedParams()); //Url encoded parameters
                writer.flush();
            }

            StringBuilder sb = new StringBuilder();
            reader = new BufferedReader(new InputStreamReader(con.getInputStream()));

            String line;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }

            return sb.toString();

        } catch (Exception e) {
            e.printStackTrace();
            return null;
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                    return null;
                }
            }
        }

    }

}

任何幫助將不勝感激。 謝謝

Answer 1

默認字母表中可能有一個“/”。

換句話說，當您運行Base64.encodeToString(b,Base64.DEFAULT) ，結果中會出現“/”，這會改變 HTTP 路徑。 我會在服務器端仔細檢查您的 HTTP 請求中的路徑。

Answer 2

我有同樣的問題。 只需使用下面的代碼就可以了：

 public class MainActivity extends AppCompatActivity {

int SELECT_PICTURE = 101;
int CAPTURE_IMAGE = 102;
Button getImage;
ImageView selectedImage;
String encodedImage;
JSONObject jsonObject;
JSONObject Response;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    getImage = (Button) findViewById(R.id.get_image);
    selectedImage = (ImageView) findViewById(R.id.selected_image);

    final AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
    builder.setTitle("Profile Picture");
    builder.setMessage("Chooose from?");
    builder.setPositiveButton("GALLERY", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            Intent intent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
            startActivityForResult(intent, SELECT_PICTURE);
        }
    });
    builder.setNegativeButton("CANCEL", null );


}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    // Check which request we're responding to
    if (requestCode == SELECT_PICTURE) {
        // Make sure the request was successful
        Log.d("Vicky","I'm out.");
        if (resultCode == RESULT_OK && data != null && data.getData() != null) {
            Uri selectedImageUri = data.getData();
            Bitmap selectedImageBitmap = null;
            try {
                selectedImageBitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), selectedImageUri);
            } catch (IOException e) {
                e.printStackTrace();
            }
            selectedImage.setImageBitmap(selectedImageBitmap);
            ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
            selectedImageBitmap.compress(Bitmap.CompressFormat.JPEG, 100, byteArrayOutputStream);
            byte[] byteArrayImage = byteArrayOutputStream.toByteArray();
            encodedImage = Base64.encodeToString(byteArrayImage, Base64.DEFAULT);
            Log.d("Vicky","I'm in.");
            new UploadImages().execute();
        }
    }
}

private class UploadImages extends AsyncTask<Void, Void, Void> {

    @Override
    protected void onPreExecute() {

    }

    @Override
    protected Void doInBackground(Void... params) {

        try {
            Log.d("Vicky", "encodedImage = " + encodedImage);
            jsonObject = new JSONObject();
            jsonObject.put("imageString", encodedImage);
            jsonObject.put("imageName", "+917358513024");
            String data = jsonObject.toString();
            String yourURL = "http://54.169.88.65/events/eventmain/upload_image.php";
            URL url = new URL(yourURL);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setDoOutput(true);
            connection.setDoInput(true);
            connection.setRequestMethod("POST");
            connection.setFixedLengthStreamingMode(data.getBytes().length);
            connection.setRequestProperty("Content-Type", "application/json;charset=UTF-8");
            OutputStream out = new BufferedOutputStream(connection.getOutputStream());
            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(out, "UTF-8"));
            writer.write(data);
            Log.d("Vicky", "Data to php = " + data);
            writer.flush();
            writer.close();
            out.close();
            connection.connect();

            InputStream in = new BufferedInputStream(connection.getInputStream());
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    in, "UTF-8"));
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line);
            }
            in.close();
            String result = sb.toString();
            Log.d("Vicky", "Response from php = " + result);
            //Response = new JSONObject(result);
            connection.disconnect();
        } catch (Exception e) {
            Log.d("Vicky", "Error Encountered");
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(Void args) {

    }
  }
}

Answer 3

這個技巧救了我的命。 我盡我所能，除了多部分數據（不需要這個）。 我的圖像被不同的編碼、Base64 編碼類型等破壞了。 所以訣竅是對你的編碼圖像字符串使用 URLEncoder：

String params = "img=" + URLEncoder.encode(base64_img_str, "UTF-8") + "&param=" + String.valueOf(someParam);

然后發送這個（使用 HttpURLConnection）：

OutputStream os = conn.getOutputStream();
                data = params.getBytes("UTF-8");
                os.write(params);
                os.flush();