Android向PHP发送数据不'；有时我不会像预期的那样回来

我已经编写了一个Android应用程序，它连接到一个PHP文件。 一切都是正确的，我已经测试过了。 有时PHP文件不返回任何内容。 当我在正常工作的浏览器中测试Android应用程序时，这是真的。 我看不出两种不同模式之间有什么共同之处

获取发送数据的方法：

private class GetData extends AsyncTask<String, String, String> {

    private ProgressDialog pDialog;
    private InputStream is = null;
    private String url;
    private String page_output = "";
    public String where;

    public GetData(String where, String UrlSend) {
        this.url    = UrlSend;
        this.where  = where;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();

        pDialog = new ProgressDialog(MainActivity.this);

        String title = "Please Wait ...";
        String content = "Please Wait ...";

        SpannableString stitle=  new SpannableString(title);
        stitle.setSpan(new RelativeSizeSpan(1f), 0, stitle.length(), 0);
        stitle.setSpan(new ForegroundColorSpan(Color.DKGRAY), 0, stitle.length(), 0);

        SpannableString scontent=  new SpannableString(content);
        scontent.setSpan(new RelativeSizeSpan(1f), 0, scontent.length(), 0);
        scontent.setSpan(new ForegroundColorSpan(Color.DKGRAY), 0, scontent.length(), 0);

        //pDialog.setTitle(stitle);
        pDialog.setMessage(scontent);
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }

    @Override
    protected String doInBackground(String... args) {

        try {
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpGet httpGet = new HttpGet(url);
            HttpResponse httpResponse = httpClient.execute(httpGet);
            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();
            page_output = sb.toString();
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result->" + e.toString());
        }

        return page_output;
    }

    @Override
    protected void onPostExecute(String page_output) {
        pDialog.dismiss();
        try {
            // display output of internet page (page_output string)
            new analyzeResponse(where, page_output).HandleResponse();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

private class GetDataPost extends AsyncTask<String, String, String> {

    private ProgressDialog pDialog;
    private InputStream is = null;
    private String url;
    private String page_output = "";
    public String where;
    public String[] PK;
    public String[] PD;

    public GetDataPost (String where, String UrlSend, String[] PostKey, String[] PostData) {
        this.url    = UrlSend;
        this.where  = where;
        this.PK         = PostKey;
        this.PD         = PostData;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();

        pDialog = new ProgressDialog(MainActivity.this);

        String title = "Please Wait ...";
        String content = "Please Wait ...";

        SpannableString stitle=  new SpannableString(title);
        stitle.setSpan(new RelativeSizeSpan(1f), 0, stitle.length(), 0);
        stitle.setSpan(new ForegroundColorSpan(Color.DKGRAY), 0, stitle.length(), 0);

        SpannableString scontent=  new SpannableString(content);
        scontent.setSpan(new RelativeSizeSpan(1f), 0, scontent.length(), 0);
        scontent.setSpan(new ForegroundColorSpan(Color.DKGRAY), 0, scontent.length(), 0);

        //pDialog.setTitle(stitle);
        pDialog.setMessage(scontent);
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }

    @Override
    protected String doInBackground(String... args) {

        try {
            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();

            for (int i = 0; i < this.PK.length; i++) {
                params.add(new BasicNameValuePair(this.PK[i], this.PD[i]));
            }

            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.setEntity(new UrlEncodedFormEntity(params, "UTF-8"));

            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();
            page_output = sb.toString();
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.toString());
        }

        return page_output;
    }

    @Override
    protected void onPostExecute(String page_output) {
        pDialog.dismiss();
        try {
            // display output of internet page (page_output string)
            new analyzeResponse(where, page_output).HandleResponse();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

PHP文件工作正常

---

谢谢大家!

对于网络通信，我建议您使用截击（）。它是一个Google库，用于通过网络发送HTTP请求，而无需处理所有多线程细节

这里有一个很好的教程，以及为什么要使用它：

error_reporting(E_ALL & ~E_NOTICE & ~E_USER_NOTICE);
header('Content-Type: text/html; charset=utf-8');

require_once 'Classes/Application/App/order.php';
require_once 'Classes/Application/practical/main.php';

$result         = FALSE;
$msg            = '';

@$code_get       = $_GET['codeget'];

if (isset($code_get)) {
    if (!empty($code_get) && $code_get == 'randcode') {
        @$what_get = $_GET['whatget'];

    if ($what_get == 'confirmevoucher') {
        $voucher = $_GET['voucher'];

        $confirme_voucher = voucher::confirme_voucher($voucher);

        if ($confirme_voucher) {
            $fraction   = voucher::get_voucher_fraction($voucher);

            $result     = array (
                'result'    => TRUE,
                'fraction'  => $fraction
            );

            $result_json = json_encode($result);

            echo $result_json;
        }else {
            $result     = array (
                'result'    => FALSE
            );

            $result_json = json_encode($result);

            echo $result_json;
        }
    }
}
}else {
    $result     = array (
                    'result'    => FALSE
                );

                $result_json = json_encode($result);

                echo $result_json;
}