yii2.0 コンポーネントとは何ですか?

use yii\jui\DatePicker;

echo DatePicker::widget([
    'language' => 'zh-CN',
    'name'  => 'country',
    'clientOptions' => [
        'dateFormat' => 'yy-mm-dd',
    ],
]);use yii\jui\DatePicker;

echo DatePicker::widget([
    'language' => 'zh-CN',
    'name'  => 'country',
    'clientOptions' => [
        'dateFormat' => 'yy-mm-dd',
    ],
]);

<?php

namespace yii\components\MyClass;

use yii\base\BaseObject;

class MyClass extends BaseObject
{
    public $prop1;
    public $prop2;

    public function __construct($param1, $param2, $config = [])
    {
        // ... 在应用配置之前初始化

        parent::__construct($config);
    }

    public function init()
    {
        parent::init();

        // ... 应用配置后进行初始化
    }
}

$component = new MyClass(1, 2, ['prop1' => 3, 'prop2' => 4]);
// 方法二：
$component = \Yii::createObject([
    'class' => MyClass::className(),
    'prop1' => 3,
    'prop2' => 4,
], [1, 2])