如何根据laravel 5.6中的id检查值是否存在？

I want to check whether the menu_id consists the same order or not.

Suppose menu_id = 1 and order = 1.

Then when the user wants to add same order (i.e. 1), it must show error message.

If not the the value must be saved.

This is submenu table:

Schema::create('submenu', function (Blueprint $table) {
    $table->increments('submenu_id');
    $table->tinyInteger('status')->default(1);
    $table->unsignedInteger('menu_id');
    $table->string('name');
    $table->tinyInteger('order');
    $table->timestamps();

    $table->foreign('menu_id')
        ->references('id')
        ->on('menu')
        ->onDelete('cascade');
});

I did this to check whether the menu_id consists the order or not, however its not working.

Submenu controller -> addSubmenu() function:

$order = Input::get('order');
$menu = Input::get('menu_id');

if($menu->contains($order)){
    echo "exists";die;
} else {
    echo "no exists";die;
}

You can use laravel eloquent to acheive this. Try:

Submenu::where('order', $order)->where('menu_id', $menu)->get();