Question

我的View课程中有两位AppServiceProvider作曲家，位于：

class AppServiceProvider extends ServiceProvider
{
    public function boot()
    {
        View::composer('left', function ($view)
        {
            if (Auth::check())
            {
                $user = Auth::user();

                // Gets a list of the people the user is following
                $usersFollowing = Following::where('user_id', $user->id)
                    ->get();

                // More queries here

                View::share('usersFollowing', $usersFollowing);
            }
        });

        View::composer('right', function ($view)
        {
            if (Auth::check())
            {
                $user = Auth::user();

                // Gets a list of the people the user is following
                $usersFollowing = Following::where('user_id', $user->id)
                    ->get();

                // More queries here

                View::share('usersFollowing', $usersFollowing);
            }
        });
    }
}

如您所见，两位作曲家都请求相同的查询数据（$usersFollowing）。这两个布局（left.blade.php和right.blade.php）都在我的所有页面上调用（通过将它们包含在基本布局中）。

这个问题是页面在单页加载时请求$usersFollowing两次。它为left.blade.php调用一次查询，为right.blade.php调用一次。

我也在每个作曲家一次调用Auth::user()两次。

如何防止这些查询被同一个请求调用两次，并且只调用一次？

Answer 1

我认为将查询移到方法的顶部并在两个View组合器中使用它们很简单。这样您的查询只会运行一次。以下是我提出的这样做的方法;

class AppServiceProvider extends ServiceProvider
{
    public function boot()
    {
        $user = Auth::user();

        // Gets a list of the people the user is following
        $usersFollowing = Following::where('user_id', $user->id)
                    ->get();
        // You can use `use` keyword to access external variables inside callback function. 
        //Both of these variables will be accessible inside callback
        View::composer('left', function ($view) use ($usersFollowing,$user)
        {
            if (Auth::check())
            {

                // More queries here

                View::share('usersFollowing', $usersFollowing);
            }
        });

        View::composer('right', function ($view) use ($usersFollowing,$user)
        {
            if (Auth::check())
            {

                // More queries here

                View::share('usersFollowing', $usersFollowing);
            }
        });
    }
}

我希望这会有所帮助，您可以将此方法推广到需要此类功能的任何其他情况。

防止在每个视图编辑器

1 个答案: