如何从编辑页面 laravel 的下拉列表中获取保存的值?

How to get saved value from dropdown in edit page laravel?

edit函数的EmployeeController里面,我有这段代码

public function edit($id)
{
        $employees = Employee::find($id);
        $departmentlists = Department::pluck('id', 'name');
        return view('employees.edit', compact('employees', 'departmentlists'));
}

并在 edit.blade.php 内显示 dropdown 我有这个代码

{!! Form::open(['action' => ['EmployeeController@update', $employees->id],  'method' => 'POST', 'autocomplete' => 'off', 'class' => 'form-horizontal', 'enctype' => 'application/x-www-form-urlencoded']) !!}
                    <div class="card">
                        <div class="card-header card-header-primary">
                            <h4 {{ Form::label('', 'Change Employee Data', ['class' => 'card-title']) }}
                            </h4>
                            <p class="card-category"></p>
                        </div>
                        <div class="card-body">
                            <div class="row">
                                <div class="col-md-12 text-right">
                                    <a href="{{ route('employees.index') }}" class="btn btn-sm btn-primary" style="font-size:12px">
                                        <i class="material-icons">keyboard_backspace</i>
                                        {{ __('kembali') }}
                                    </a>
                                </div>
                            </div>
                            <div class="row">
                                {{ Form::label('Name', '', ['class' => 'col-sm-2 col-form-label']) }}
                                <div class="form-group col-sm-7">
                                    {{Form::text('name', $employees->name, ['class' => 'form-control', 'placeholder' => 'Name', 'required'])}}
                                    <p style="color: red;">@error('name') {{ $message }} @enderror</p>
                                </div>
                            </div>
                            <div class="row">
                                {{ Form::label('Department', '', ['class' => 'col-sm-2 col-form-label']) }}
                                <div class="col-md-7">
                                    <div class="form=group">
                                        @foreach($departmentlists as $dl)
                                            <option value="{{ $dl->id }}"  @if($dl->id==$employees->department_id) selected='selected' @endif >{{ $employees->name }}</option>
                                        @endforeach
                                        <p style="color: red;">@error('id') {{ $message }} @enderror</p>
                                    </div>
                                </div>
                            </div>
                            <div class="row">
                                {{ Form::label('Keterangan', '', ['class' => 'col-sm-2 col-form-label']) }}
                                <div class="form-group col-sm-7">
                                    {{ Form::textarea('information', $employees->information, ['class' => 'form-control', 'placeholder' => 'Keterangan', 'rows' => '6', 'cols' => '50']) }}
                                </div>
                            </div>
                        </div>
                        <div class="card-footer ml-auto mr-auto">
                            {{ Form::hidden('_method','PUT') }}
                            {{ Form::submit('Ubah', ['class' => 'btn btn-primary']) }}
                        </div>
                    </div>
                {!! Form::close() !!}

这是employees table 这是 departments table

现在,我的目标是让编辑页面上的下拉菜单显示员工所属的部门名称,而下拉菜单仍然包含所有部门名称。 所以我可以更改它,但是当我 运行 这段代码时它给了我这个错误。

Trying to get property 'id' of non-object (View:

C:\xampp\htdocs\ims-it-laravel7\resources\views\employees\edit.blade.php)

我已经阅读了这里的其他线程,但是那些代码仍然没有解决问题

$departmentlists = Department::pluck('id', 'name');

以后你用

@foreach($departmentlists as $dl)$dl->id

$dl 不是一个对象,它是一个数组,因为 pluck() 函数。

更准确地说,它看起来像这样

  [
    "abc" => 1
    "xyz" => 2
    "foo" => 3
  ]

注意:要亲自查看,请尝试使用 dd($departmentlists)dump($departmentlists)

请看Laravel Eloquent Pluck

在这种情况下,您可能希望使用 Department::select(['id', 'name'])->get(),因为它将 return 具有指定属性的对象集合。