Laravel: 无法添加记录多对多关系

Question

我想使用 Laravel 6 的多对多关系添加记录。我有一个用户可能有很多角色，如管理员、博主等

这是我在用户模型中的函数

public function roles()
{
    return $this->belongsToMany(
        'App\Role', 'user_roles', 'user_id', 'role_id', 'id'
    );
}

这是表单提交后的请求数据

array:5 [▼
    "_token" => "asdnkasdjisajdmasnduajid"
    "email" => "admin@admin.com"
    "roles" => array:2 [▼
        0 => "2"
        1 => "3"
    ]
]

我试过这个方法来保存我的记录

$users = [
    'name'     => $request->name,
    'email'    => $request->email,
    'password' => bcrypt($request->password),
    'status'   => 'active',
];
$user = User::create($users);

if ($user) {
    $role = $user->roles()->attach($request->roles);
    if (!$role) {
        Session::flash('error', "Unable to create Role at this moment");

        return redirect()->back();
    }
    Session::flash('status', 'User Created Successfully');

    return redirect()->back();
}

我得到

Unable to create Role at this moment

Answer 1

多对多关系doesn't return anything的attach()方法。因此，您的角色变量将始终为空，即使角色已成功附加到用户。

试试这个：

$users = [
    'name'     => $request->name,
    'email'    => $request->email,
    'password' => bcrypt($request->password),
    'status'   => 'active',
];

$user = User::create($users);

if (!$user instanceof User) {
    Session::flash('error', "Unable to create User at this moment");
    return redirect()->back();
}

$user->roles()->attach($request->roles);

if (!$user->roles) {
    Session::flash('error', "Unable to create Role at this moment");
    return redirect()->back();
}

Session::flash('status', 'User Created Successfully');
return redirect()->back();

Laravel: 无法添加记录多对多关系

Laravel: Unable To Add Record Many to many Relationship

laravel

eloquent

laravel-6