即使结果与 if 语句匹配，Android 也会'else'

Question

我正在开发一个Android应用程序。在我的代码的特定部分中，即使满足语句的if语句，其他选项始终执行。任何帮助将受到高度赞赏。这是我的代码：

php：

<?php
error_reporting(0);
include 'conexao.php';
$usuario = $_POST["username"];
$senha   = $_POST["password"];
$result   = mysql_query("select * from login where usuario = '" . $usuario . "' and senha = '" . $senha . "';");
$num_rows = mysql_num_rows($result);
if ($num_rows == 0) {
    echo 'false';
} else if ($num_rows == 1) {
    echo 'true';
} else {
    echo 'nenhum';
}
?>

和我的java：

EditText txtusuario, txtsenha;
Button btnlogin;
public static final int CONNECTION_TIMEOUT=10000;
public static final int READ_TIMEOUT=15000;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login);
    txtusuario = (EditText) findViewById(R.id.txtusuario);
    txtsenha = (EditText) findViewById(R.id.txtsenha);
    btnlogin = (Button) findViewById(R.id.btnlogin);
    btnlogin.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            // Get text from email and passord field
            final String username = txtusuario.getText().toString();
            final String password = txtsenha.getText().toString();
            // Initialize  AsyncLogin() class with email and password
            new AsyncLogin().execute(username,password);
        }
    });
}
private class AsyncLogin extends AsyncTask<String, String, String>
{
    ProgressDialog pdLoading = new ProgressDialog(LoginActivity.this);
    HttpURLConnection conn;
    URL url = null;
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        //this method will be running on UI thread
        pdLoading.setMessage("tLoading...");
        pdLoading.setCancelable(false);
        pdLoading.show();
    }
    @Override
    protected String doInBackground(String... params) {
        try {
            // Enter URL address where your php file resides
            url = new URL("http://rhynotcc.hol.es/teste/login.php");
        } catch (MalformedURLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return "exception";
        }
        try {
            // Setup HttpURLConnection class to send and receive data from php and mysql
            conn = (HttpURLConnection)url.openConnection();
            conn.setReadTimeout(READ_TIMEOUT);
            conn.setConnectTimeout(CONNECTION_TIMEOUT);
            conn.setRequestMethod("POST");
            // setDoInput and setDoOutput method depict handling of both send and receive
            conn.setDoInput(true);
            conn.setDoOutput(true);
            // Append parameters to URL
            Uri.Builder builder = new Uri.Builder()
                    .appendQueryParameter("username", params[0])
                    .appendQueryParameter("password", params[1]);
            String query = builder.build().getEncodedQuery();
            // Open connection for sending data
            OutputStream os = conn.getOutputStream();
            BufferedWriter writer = new BufferedWriter(
                    new OutputStreamWriter(os, "UTF-8"));
            writer.write(query);
            writer.flush();
            writer.close();
            os.close();
            conn.connect();
        } catch (IOException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
            return "exception";
        }
        try {
            int response_code = conn.getResponseCode();
            // Check if successful connection made
            if (response_code == HttpURLConnection.HTTP_OK) {
                // Read data sent from server
                InputStream input = conn.getInputStream();
                BufferedReader reader = new BufferedReader(new InputStreamReader(input));
                StringBuilder result = new StringBuilder();
                String line;
                while ((line = reader.readLine()) != null) {
                    result.append(line);
                }
                // Pass data to onPostExecute method
                return(result.toString());
            } else {
                return("unsuccessful");
            }
        } catch (IOException e) {
            e.printStackTrace();
            return "exception";
        } finally {
            conn.disconnect();
        }
    }
    @Override
    protected void onPostExecute(String result) {
        //this method will be running on UI thread
        pdLoading.dismiss();
        String teste = "true";
        if(result.equals(teste)) {
            //Notificação para saber o resultado do login
            int a = 0;
            NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(LoginActivity.this);
            mBuilder.setSmallIcon(R.drawable.escavadeira);
            mBuilder.setContentTitle("Notificação");
            mBuilder.setContentText("Conexão deu certo caralho" + result);
            NotificationManager mNot = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
            mNot.notify(a, mBuilder.build());
        } else {
            int a = 0;
            NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(LoginActivity.this);
            mBuilder.setSmallIcon(R.drawable.escavadeira);
            mBuilder.setContentTitle("Notificação");
            mBuilder.setContentText("Deu errado" + result);
            NotificationManager mNot = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
            mNot.notify(a, mBuilder.build());
        }
    }
}

当我的通知中的结果是" deu errado true"，当时应该是if语句，我已经尝试了 result.equals("true")

Answer 1

if ($num_rows == 0) {
    echo 'false';
} else if ($num_rows == 1) {
    echo 'true';
} else {
    echo 'nenhum';
}

而不是确保您的代码应该像

一样

if ($num_rows) {
    echo 'false';
} else {
    echo 'nenhum';
}

Answer 2

@Override
protected void onPostExecute(String result) {
  super.onPostExecute(result);
  //this method will be running on UI thread
  pdLoading.dismiss();
  String teste = "true";
  int a = 0;
  NotificationCompat.Builder mBuilder = new
  NotificationCompat.Builder(LoginActivity.this);
  mBuilder.setSmallIcon(R.drawable.escavadeira);
  mBuilder.setContentTitle("Notificação");
  if (result.equals(teste)) {
    //Notificação para saber o resultado do login
    mBuilder.setContentText("Conexão deu certo caralho" + result);
  } else {
    mBuilder.setContentText("Deu errado" + result);
  }
  NotificationManager mNot = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
  mNot.notify(a, mBuilder.build());
}