Android 登录注册：无法使用 volley 将数据插入数据库

Question

伙计们我陷入了困境。使用 volley，我尝试在 000webhost 上的数据库中创建用户。因此我使用这个 Register.php

<?php
    $connect = mysqli_connect("localhost", "id6777294_l2w", "123l2w456", "id6777294_l2w");
    
if(isset($_POST["name"]) && isset($_POST["email"]) && isset($_POST["password"]) && isset($_POST["grade"])){
    $name = $_POST["name"];
    $email = $_POST["email"];
    $password = $_POST["password"];
    $class = $_POST["grade"];
}

    $statement = mysqli_prepare($connect, "INSERT INTO user(name, email, password, grade) VALUES (?, ?, ?, ?)");
    mysqli_stmt_bind_param($statement, "sssi", $name, $email, $password, $grade);
    mysqli_stmt_execute($statement);
    
    $response = array();
    $response["success"] = true;  
    
    echo json_encode($response);
?>

和后面两个android类

public class RegisterActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);

        final EditText nameID = (EditText) findViewById(R.id.nameID);
        final EditText emailID = (EditText) findViewById(R.id.emailID);
        final EditText passwordID = (EditText) findViewById(R.id.passwordID);
        final EditText gradeID = (EditText) findViewById(R.id.gradeID);
        final Button registerbtn = (Button) findViewById(R.id.registerbtn);

        registerbtn.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

                //we need to get the data given by the user
                final String name = nameID.getText().toString();
                final String email = emailID.getText().toString();
                final String password = passwordID.getText().toString();
                final int grade = Integer.parseInt(gradeID.getText().toString());

                //now we need a String Listener for the constructor
                Response.Listener<String> responseListener = new Response.Listener<String>() {

                    /**
                     * everything in here happens when the response listener has been executed,
                     * given the response (which comes as a JSON String) from the Register.php.
                     * If the response is not in the form of a JSON format, then JSONException
                     * will catch the error
                     */

                    @Override
                    public void onResponse(String response) {
                        try {
                            JSONObject jsonResponse = new JSONObject(response);
                            boolean success = jsonResponse.getBoolean("success");

                            //if successful then go back to LoginActivity, if not make an alert
                            if (success){
                                Intent intent = new Intent(RegisterActivity.this, LoginActivity.class);
                                RegisterActivity.this.startActivity(intent);
                            }else {
                                AlertDialog.Builder builder = new AlertDialog.Builder(RegisterActivity.this);
                                builder.setMessage("Registrierung fehlgeschlagen").setNegativeButton("Wiederhole",null).create().show();

                            }


                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

                    }
                };

                //this actual creates the request we need for registration
                RegisterRequest registerRequest = new RegisterRequest(name, email, password, grade, responseListener);
                RequestQueue queue = Volley.newRequestQueue(RegisterActivity.this);
                queue.add(registerRequest);
            }
        });


    }
}

public class RegisterActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);

        final EditText nameID = (EditText) findViewById(R.id.nameID);
        final EditText emailID = (EditText) findViewById(R.id.emailID);
        final EditText passwordID = (EditText) findViewById(R.id.passwordID);
        final EditText gradeID = (EditText) findViewById(R.id.gradeID);
        final Button registerbtn = (Button) findViewById(R.id.registerbtn);

        registerbtn.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {

                //we need to get the data given by the user
                final String name = nameID.getText().toString();
                final String email = emailID.getText().toString();
                final String password = passwordID.getText().toString();
                final int grade = Integer.parseInt(gradeID.getText().toString());

                //now we need a String Listener for the constructor
                Response.Listener<String> responseListener = new Response.Listener<String>() {

                    /**
                     * everything in here happens when the response listener has been executed,
                     * given the response (which comes as a JSON String) from the Register.php.
                     * If the response is not in the form of a JSON format, then JSONException
                     * will catch the error
                     */

                    @Override
                    public void onResponse(String response) {
                        try {
                            JSONObject jsonResponse = new JSONObject(response);
                            boolean success = jsonResponse.getBoolean("success");

                            //if successful then go back to LoginActivity, if not make an alert
                            if (success){
                                Intent intent = new Intent(RegisterActivity.this, LoginActivity.class);
                                RegisterActivity.this.startActivity(intent);
                            }else {
                                AlertDialog.Builder builder = new AlertDialog.Builder(RegisterActivity.this);
                                builder.setMessage("Registrierung fehlgeschlagen").setNegativeButton("Wiederhole",null).create().show();

                            }


                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

                    }
                };

                //this actual creates the request we need for registration
                RegisterRequest registerRequest = new RegisterRequest(name, email, password, grade, responseListener);
                RequestQueue queue = Volley.newRequestQueue(RegisterActivity.this);
                queue.add(registerRequest);
            }
        });


    }
}

我没有收到任何错误或来自 logcat 等的提示。当我单击“注册”按钮时，我回到了 LoginActivity，这看起来很完美。但是当使用 phpmyadmin 检查数据库时，"user" 数据中没有新条目。

请帮忙，我做了所有建议的改进并清除了常见错误，但它不会存储数据...

Answer 1

在您的绑定参数语句中，您正在传递参数 $grade，但我没有看到 $grade 变量已初始化，您是要传递 $class 吗？可能是检查的开始。

Android 登录注册：无法使用 volley 将数据插入数据库

Android Login Register: Cant insert data into a database using volley

java

android

phpmyadmin

android-volley

registration