yii2框架中使用下拉菜单的自动搜索yii-widget-select2

php composer.phar require kartik-v/yii2-widget-select2 "*"

引用方法：use kartik\select2\Select2;

源代码：

<?= $form->field($model, 'companies_company_id')->widget(Select2::classname(), [
'data' => ArrayHelper::map(Companies::find()->all(),'company_id','company_name'),
'language' => 'en',
'options' => ['placeholder' => 'Select a state ...'],
'pluginOptions' => [
'allowClear' => true
],
]); ?>

相关内容的详细解释：http://demos.krajee.com/widget-details/select2