问如何区分rest中的两个变量

EN

public function showEditIndex($id=null,$ajax=null) 
    {

        $article = new \stdClass();
        $article->id = "";
        $article->title = "";
        $article->content = "";
        $article->date = "";

        if($id != null){
            $tmp = DB::select('select * from blog where id = '.$id);
            $article->id = $tmp[0]->id;
            $article->title = $tmp[0]->title;
            $article->content = $tmp[0]->content;
            $article->date = $tmp[0]->date;
        }

        if($ajax=='ajax'){ //Ajoute ou Modifie

            $title = Input::get('title');
            $content = Input::get('content');
            $date = Input::get('date');
            if($date != null){
                $query = DB::table('users')
                    ->where('id', 1)
                    ->update(['title' => $title,'content' => $content, $date => date("F j, Y \a\t g:ia")]);
                return;
            }

            $query = DB::table('blog')->insertGetId(
                array('title' => $title, 'content' => $content)
            );

            return $query;
        }

        return view('blog.add')
        ->with('article',$article)
        ->withTitle('Edit Article');
    }