Question

有必要在listBoxt字段中有一个占位符，例如“为用户选择角色”，即用户看到而未在列表框中选择任何内容的消息。但这应包括选项'prompt' => 'remove the role'，以便用户可以通过下拉列表删除角色。

是否可以通过标准的Yii功能而不使用JS来做到这一点？

echo $form->field($model, 'additionalRoles', [
  'options' => [
    'class' => 'form-group',
  ],
])->listBox($additionalRoles, [
  'class'  => 'form-control j-multi-select2',
  'prompt' => 'Select additional role',
]);

例如：https://jsfiddle.net/8e7avn2d/1/

Answer 1

<?=
$form->field($model, 'additionalRoles', [
    'options' => [
        'class' => 'form-group',
    ],
])
->listBox($additionalRoles, [
    'class' => 'form-control j-multi-select2',
    'prompt' => [
        'text' => "Select additional role",
        'options' => [
            'disabled' => true,
            'selected' => true,
            'hidden' => true,
        ]]
]);
?>

Answer 2

要获得您的示例，您应该使用dropDownList而不是listBox

echo $form->field($model, 'additionalRoles', [
  'options' => [
    'class' => 'form-group',
  ],
])->dropDownList($additionalRoles, [
  'class'  => 'form-control j-multi-select2',
  'prompt' => 'Select additional role',
]);

如何在列表框中放置一个占位符

2 个答案: