控制器

public function actionCreate() {
    $model = new Ceremonia();
  if ($this->request->isPost) {
     if ($model->load($this->request->post()) && $model->save()){ Yii::$app->getSession()->setFlash('info',[' Nombre <strong>insertado</strong> correctamente!!!']); return $this->redirect(['index']); 
   }}else{ $model->loadDefaultValues();}
  if(Yii::$app->request->isAjax) { 
    return $this->renderAjax('create',['model' => $model]); }else{ return $this->render('create',['model' => $model]); 
   }
 }

项目中的索引文件：索引

<?= Html::button('<i class="fas fa-plus"></i> Insertar',['value'=>Url::to('create'),'class' => 'btn btn-info','data-toggle'=>'modal','data-target'=>' ajax','id'=>'ModalButtonCreate']); ?>

<?php  
  Modal::begin(['title'=>'Insertar', 'id'=>'modalCreate', /*'size'=>'modal-lg',*/]);
  echo '<div id="modalContentCreate"></div>';
  Modal::end();
?>

项目中的main.js文件：主文件.js

$(function(){
 $('#ModalButtonCreate').click(function(){  
     $('#modalCreate').modal('show').find('#modalContentCreate').load($(this).attr('value'));
  }); 
});

项目中的AppAsset文件：应用程序资产

class AppAsset extends AssetBundle {
     public $basePath = '@webroot';
     public $baseUrl = '@web';
     public $css = ['css/site.css',];
     public $js = ['js/main.js',];
     public $depends = ['yii\web\YiiAsset','yii\bootstrap4\BootstrapAsset',]; 
  }