CakePHP 保存 HABTM 数据

CakePHP是一个流行的PHP开发框架，它提供了许多方便的功能来简化开发过程。其中之一是它支持保存HABTM（Has and Belongs to Many）数据的能力。本文将介绍如何使用CakePHP保存HABTM数据，并提供一个示例代码。

php
class Student extends AppModel {
    public $hasAndBelongsToMany = array(
        'Course' => array(
            'className' => 'Course',
            'joinTable' => 'students_courses',
            'foreignKey' => 'student_id',
            'associationForeignKey' => 'course_id',
            'unique' => 'keepExisting',
        )
    );
}

php
class Course extends AppModel {
    public $hasAndBelongsToMany = array(
        'Student' => array(
            'className' => 'Student',
            'joinTable' => 'students_courses',
            'foreignKey' => 'course_id',
            'associationForeignKey' => 'student_id',
            'unique' => 'keepExisting',
        )
    );
}

php
$this->Student->id = $studentId;
$this->Student->save($this->request->data);

php
// 学生控制器
class StudentsController extends AppController {
    public function add() {
        if ($this->request->is('post')) {
            $this->Student->create();
            if ($this->Student->save($this->request->data)) {
                $this->Flash->success(__('The student has been saved.'));
                return $this->redirect(array('action' => 'index'));
            } else {
                $this->Flash->error(__('The student could not be saved. Please, try again.'));
            }
        }
        $this->set('courses', $this->Student->Course->find('list'));
    }
}
// 学生模型
class Student extends AppModel {
    public $hasAndBelongsToMany = array(
        'Course' => array(
            'className' => 'Course',
            'joinTable' => 'students_courses',
            'foreignKey' => 'student_id',
            'associationForeignKey' => 'course_id',
            'unique' => 'keepExisting',
        )
    );
}
// 课程模型
class Course extends AppModel {
    public $hasAndBelongsToMany = array(
        'Student' => array(
            'className' => 'Student',
            'joinTable' => 'students_courses',
            'foreignKey' => 'course_id',
            'associationForeignKey' => 'student_id',
            'unique' => 'keepExisting',
        )
    );
}