ThinkPHP框架怎么使用模型关联_ThinkPHP关联查询与预加载优化

// app/model/User.php
class User extends Model 
{
    public function articles()
    {
        return $this->hasMany(Article::class, 'user_id', 'id');
    }
}

// app/model/Article.php
class Article extends Model 
{
    public function user()
    {
        return $this->belongsTo(User::class, 'user_id', 'id');
    }
}

$user = User::find(1);
foreach ($user->articles as $article) {
    echo $article->title;
}

// 使用hasWhere进行关联条件查询
$users = User::hasWhere('articles', function($query){
    $query->where('title', 'like', '%PHP%');
})->select();

$users = User::with(['articles' => function($query) {
    $query->where('status', 1);
}])->select();

// 正确使用预加载
$users = User::with('articles')->select();

foreach ($users as $user) {
    foreach ($user->articles as $article) {
        echo $article->title;
    }
}

$users = User::with(['articles', 'profile'])->select();

$users = User::with('articles.comments')->select();