Laravel 5.1如何将对象的ID传递给另一个视图以用作另一个表中的外键？

Question

I have a projects table and a quotes table with the following structure:

Schema::create('quotes', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('project_id')->index()->unsigned();
            $table->decimal('quote', 10,0);
            $table->timestamps();

On the project page I need a link which refers to the page for creating a new quote. How can I pass the id of a project to the create view of a quote?

UPDATE

I tried flashing the project id to the session an then getting it in the quote controller but by the time I'm trying to get it there the session is emty!

//flashing project_id to the session
        $request->session()->flash('project_id', $project->id);
or
        $request->session()->flash('project_id', $project->id);
        $request->session()->reflash();
or
        $request->session()->flash('project_id', $project->id);
        $request->session()->keep(['project_id']);;
//getting it in quote controller
        $project_id=$request->session()->get('project_id');

what is the problem?

Answer 1

Suppose that U have a Project model and $project is an instance of it. Get Id of the project and pass it to the quote view like this:

$project_id = $project->id;
return redirect()->intended('your_view')->with('project_id' , $project_id);

the $project_id is stored in the sessions. So you can easily retrieve it like this in the blade:

if(session()->has('project_id')){
    $project_id = session('project_id');
    // do whatever u want with the $project_id and set it in quote table
}

Answer 2

First, you can define resourceful routes like this:

Route::resource('projects.quotes', 'QuotesController');

Now, in your project page place this code where you want to display the link to create quotes:

{!! link_to_route('projects.quotes.create', 'Create Quote', $project->id) !!}

Now, modify your QuotesController's create function like this:

public function create($project_id)
{
    $project = App\Project::find($project_id);
    return view('quotes.create', compact('project'));
}

Now, you can use $project data in your create.php or create.blade.php view file

Answer 3

Laravel allows you to share variables between views. You can add it to the existing AppServiceProvider or create your own.

In the selected service provider:

public function boot()
{
    view()->share('username','Joe');
}

The variable $username is available to all views. You can also call share method from the controller or anywhere before you render the view.

View::share('key','value');

Hope this help

Answer 4

I found a solution which worked.In the show method of projects controller I used the put() method to flash the project->id to the session:

$request->session()->put('project_id', $project->id);

then in the create method of quotes controller I used the pull() method to get the project_id out of session.

$id=$request->session()->pull('project_id');

But there was a little problem with this approach, and in case the user decides to refresh the form page there will be no project_id key in session. To tackle this I decided to redirect the user to the list of projects to select one again.