按角色Laravel筛选用户

// User.php
class User extends Authenticatable
{
    public function roles()
    {
        return $this->belongsToMany(Role::class);
    }
}

// Role.php
class Role extends Model
{
    public function users()
    {
        return $this->belongsToMany(User::class);
    }
}

Schema::create('role_user', function (Blueprint $table) {
    $table->id();
    $table->unsignedBigInteger('user_id');
    $table->unsignedBigInteger('role_id');
    $table->timestamps();

    $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
    $table->foreign('role_id')->references('id')->on('roles')->onDelete('cascade');
});

use App\Models\User;
use App\Models\Role;

// 获取具有特定角色的所有用户
$roleName = 'admin';
$usersWithRole = User::whereHas('roles', function ($query) use ($roleName) {
    $query->where('name', $roleName);
})->get();

// 或者使用Eloquent关系直接查询
$role = Role::where('name', $roleName)->first();
$usersWithRole = $role ? $role->users : collect();

$usersWithRole = User::with('roles')->whereHas('roles', function ($query) use ($roleName) {
    $query->where('name', $roleName);
})->get();