laravel gets url parameters

<code><span><?php</span><span>namespace</span><span>App</span>\<span>Http</span>\<span>Controllers</span>;

<span>use</span><span>App</span>\<span>Article</span>;
<span>use</span><span>Carbon</span>\<span>Carbon</span>;
<span>use</span><span>App</span>\<span>Http</span>\<span>Requests</span>\<span>Request</span>;
<span>use</span><span>Illuminate</span>\<span>Support</span>\<span>Facades</span>\<span>DB</span>;

<span><span>class</span><span>ArticleController</span><span>extends</span><span>Controller</span>
{</span><span>public</span><span><span>function</span><span>demo</span><span>(Request <span>$request</span>)</span>
    {</span><span>//        return $request->all();</span><span>return</span><span>$request</span>->input(<span>"aa"</span>);
    }



}
</code>