Laravel 5将数据库查询从控制器传递到视图

I'm new to Laravel 5 and MVC frameworks in general. I having trouble getting results from a database query and passing it to my blade view. Here is what I have for a controller function ...

public function show(Project $project)
{
$technologies = DB::select('select * from technologies where id = ?', [$project->technology_id]);
return view('projects.show', compact('project','technologies'));
}

and my view is ...

@section('content')
   <h2>{{ $project->name }}</h2>

    @if ( !technologies() )
        no technologies.
    @else
        <ul>
            @foreach( $technologies as $technology )
                <li><a href="#">{{ $technology->slug }}</a></li>
            @endforeach
        </ul>
    @endif
@endsection

Thanks for your help

controller

public function show(Project $project)
{
    $technologies = DB::table('technologies')
        ->select('*')
        ->where('id', $project->technology_id)
        ->get(); // you were missing the get method

    return view('projects.show', compact('project', 'technologies'));
}

View

This will not work in your view: @if ( !technologies() )

@section('content')

<h2>{{ $project->name }}</h2>
    @if($technologies)
        <ul>
            @foreach($technologies as $technology)
                <li><a href="#">{{ $technology->slug }}</a></li>
            @endforeach
        </ul>
    @else
        <p>no technologies.</p>
    @endif
@stop

Also, if you're interested in a cleaner way to loop through your data or show a 'no data' warning using blade check out this article which uses blade's @each https://laravel-news.com/2014/09/laravel-blade/

rewrite your query as,

$technologies = DB::table('technologies')->where('id',$project->technology_id)->get();