Laravel Sync方法仅发送第二个数据

Question

This piece of code should be deleting all old data from the database and when add the new ones (using sync())

Now I have a project with users, and a user can be linked to a project with a checkbox.

So on checkbox checked this function will trigger, but for example when I say that user 1 and user 2 are going through this fuction to get added to the pivot table it will only send user 2 , and user 1 will not get through, what is going wrong?

And when I add 3 users user 1 , user 2 , user 3 , only user 2 will get added.

Controller

public function update(CreateProjectRequest $request)
{
    if($request->get('contribute'))
    {
        foreach($request->get('contribute') as $k => $contribute)
        {
            if($contribute == 1)
            {
                $project = $this->project->find($request->project_id);
                $project->users()->sync(array($k));

            }
        }
    }

    $project = $this->project->find($request->project_id);
    $project->fill($request->input())->save();

    return redirect('project');
}

Blade

@foreach($users as $user)
            <tr>
                <td>
                    {{$user->firstname}} {{$user->middlename}} {{$user->lastname}}
                </td>
                <td>
                    {!! Form::checkbox('contribute['.$user->id.']', '1', $user->projects->contains('id', $project->id)) !!}
                </td>
            </tr>
@endforeach

On a dd($request->input()); at the start of my update method (with selecting atleast 3 users) this will get in return:

  array:9 [▼
  "_method" => "PATCH"
  "_token" => "0uIZNn6zwZjVKfgE0ckhDULeYda0OaLzKVdUgoM8"
  "name" => "Dire Straits"
  "completion_date" => "2015-05-18"
  "DataTables_Table_0_length" => "10"
  "contribute" => array:3 [▼
    1 => "1"
    3 => "1"
    2 => "1"
  ]
  "completed" => "1"
  "active" => "0"
  "project_id" => "11"
]

So 1 / 3 / 2 would be the user_id and => 1 should be the value.

Answer 1

The problem is that sync gets called in loop 3 times so each time it's syncing one value. You have to pass an array of the ids in sync ex:

$project->users()->sync([1,3,2]);

Or if you want you can use attach when contribute==1 and detach when contribute==0

Or if contribute doesnt return input when a user is deselected and it only returns when it is selected then you can try:

$this->project->users()->sync(array_keys($request->get('contribute'));

I just noticed that you have another bug unless you are updating many projects with one call you should put the line below on the first line of your function.

$project = $this->project->find($request->project_id);