使用android中的HttpURLConnection將帶有參數的圖像發送到服務器

Question

我試圖通過我的Android應用程序將兩個圖像以及一些參數上傳到服務器。 在網上搜索並按照此處 ， 此處以及其他來源的說明進行操作之后，我得到了以下代碼：

String boundary = "***" + System.currentTimeMillis() + "***";
String twoHyphens = "--";
String crlf = "\r\n";
String output = "";
try {
            HttpURLConnection httpUrlConnection = null;
            URL url = new URL(myUrl);
            httpUrlConnection = (HttpURLConnection) url.openConnection();
            httpUrlConnection.setUseCaches(false);
            httpUrlConnection.setDoInput(true);
            httpUrlConnection.setDoOutput(true);
            httpUrlConnection.setRequestMethod("POST");

            httpUrlConnection.setRequestProperty("Connection", "Keep-Alive");
            httpUrlConnection.setRequestProperty("Cache-Control", "no-cache");
            httpUrlConnection.setRequestProperty("ENCTYPE", "multipart/form-data");
            httpUrlConnection.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);


            DataOutputStream request = new DataOutputStream(httpUrlConnection.getOutputStream());
            request.writeBytes(twoHyphens + boundary + crlf);

            // Convert and add first image
            ByteArrayOutputStream bao1 = new ByteArrayOutputStream();
            params[0].compress(Bitmap.CompressFormat.JPEG, 100, bao1);
            byte[] ba1 = bao1.toByteArray();


            request.writeBytes("Content-Disposition: form-data; name=\"image1\";filename=\"image1\"" + crlf);
            request.writeBytes(crlf);
            request.write(ba1);
            request.writeBytes(crlf);
            request.writeBytes(twoHyphens + boundary + crlf);

            // Convert and add second image
            ByteArrayOutputStream bao2 = new ByteArrayOutputStream();
            params[1].compress(Bitmap.CompressFormat.JPEG, 100, bao2);
            byte[] ba2 = bao2.toByteArray();

            request.writeBytes("Content-Disposition: form-data; name=\"image2\";filename=\"image2\"" + crlf);
            request.writeBytes(crlf);
            request.write(ba2);
            request.writeBytes(crlf);
            request.writeBytes(twoHyphens + boundary + crlf);

            request.writeBytes("Content-Disposition: form-data; name=\"username\"" + crlf);
            request.writeBytes(crlf);
            request.writeBytes(username);
            request.writeBytes(crlf);
            request.writeBytes(twoHyphens + boundary + twoHyphens);

            request.writeBytes("Content-Disposition: form-data; name=\"datestr\"" + crlf);
            request.writeBytes(crlf);
            request.writeBytes(timeStampString);
            request.writeBytes(crlf);
            request.writeBytes(twoHyphens + boundary + twoHyphens);

            request.flush();
            request.close();

            int responseCode = httpUrlConnection.getResponseCode();
            if (responseCode == HttpsURLConnection.HTTP_OK) {
                InputStream responseStream = new BufferedInputStream(httpUrlConnection.getInputStream());
                BufferedReader responseStreamReader = new BufferedReader(new InputStreamReader(responseStream, Charset.forName("UTF-8")));

                String line;
                while ((line = responseStreamReader.readLine()) != null) {
                    output = line;
                    Log.d(TAG, line);
                }
                responseStreamReader.close();
            }
            httpUrlConnection.disconnect();

            if (output == "") {
                httpResultsReturned = false;
            } else {
                httpResultsReturned = true;
            }

        } catch (ProtocolException e) {
            e.printStackTrace();
            return "failed";
        } catch (MalformedURLException e) {
            e.printStackTrace();
            return "failed";
        } catch (IOException e) {
            e.printStackTrace();
            return "failed";
        }

在服務器端，我嘗試按以下方式訪問數據：

<?php

if($_SERVER['REQUEST_METHOD'] === 'POST'){
    $image1 = $_FILES['image1']['name'];
    $image2 = $_FILES['image2']['name'];
    $datestr= $_POST['datestr'];
    $username= $_POST['username'];
}

?>

最終，兩個圖像都成功傳輸，但是我無法發送/接收額外的參數。 我正確地收到了響應，但是在所有的php代碼中（有部分我在此問題中省略了），似乎沒有參數被發送/接收。

在這個問題中，AndroSco共享了對他有用的解決方案，但是在他的php文件中，看來他僅訪問圖像而不是參數...

由於我在該領域沒有很多經驗，因此我認為可能很明顯我做錯了/根本沒有做！

任何建議將不勝感激！

謝謝！

Answer 1

沮喪之后，我在代碼中找到了該錯誤。 將兩個圖像導入傳輸的消息中之后，並且當我想導入其他參數時，我錯誤地編寫了邊界。 而不是添加以下內容：

request.writeBytes(twoHyphens + boundary + crlf);

在結尾有新行，我這樣寫：

request.writeBytes(twoHyphens + boundary + twoHyphens);

在行尾添加兩個連字符。

更換后twoHyphens與crlf ，一切工作很好！