在 blade 上使用 select/drop-down 渲染空值

Question

来自 "Form" laravelcollective 手册：

Generating a Drop-Down List With an Empty Placeholder This will create an "option" element with no value as the very first option of your drop-down.

echo Form::select('size', ['L' => 'Large', 'S' => 'Small'], null, ['placeholder' => 'Pick a size...']);

我在 blade 页面上的代码：

{{ Form::select('company_id', $companies->pluck('name','id'), null , ['id'=>'company_id','class' => 'form-control']) }}

它呈现：

<select id="company_id" class="form-control" name="company_id">
     <option value="1">azienda1</option>
     <option value="2">azienda2</option>
</select>

为什么没有空值？我哪里错了？提前致谢！

Answer 1

示例中的null值是设置初始值，不是设置占位符

手册上说 ['placeholder' => 'Pick a size...']) 是占位符。

要添加空占位符，您应该能够执行以下操作：

{{ Form::select('company_id', $companies->pluck('name','id'), null , ['id'=>'company_id','class' => 'form-control', 'placeholder' => '']) }}

在 blade 上使用 select/drop-down 渲染空值

render a null value with a select/drop-down on blade

forms

laravel

drop-down-menu

laravel-blade