Yii2 开发小技巧

$query = User::find()->where(['LIKE', 'name', 'php%', false]);
$commandQuery = clone $query;
// SELECT * FROM `user` WHERE `name` LIKE 'php%'
echo $commandQuery->createCommand()->getRawSql();

return \yii\helpers\ArrayHelper::getColumn(User::find()->all(), 'name');
return User::find()->select('name')->asArray()->column();

* 使用`find_in_set()`等函数，需要用到`Expression()` 表达式。

User::find()
    ->where(new yii\db\Expression('FIND_IN_SET(:status, status)'))
    ->addParams([':status' => 1])
    ->all();

* 避免select里的子查询被识别成字段

$quert = User::find()
    ->select([
          new Expression('count(*) as count , count(distinct mobile) as mnumber')
     ])->asArray()
    ->all();

$transaction = $connection->beginTransaction();
try {
    $connection->createCommand($sql1)->execute();
    $connection->createCommand($sql2)->execute();
    // ... 执行其他 SQL 语句 ...
    $transaction->commit();
} catch(Exception $e) {
    $transaction->rollBack();
    throw $e;
}

[
    ['store_id', 'member_name'],
    'unique',
    'targetAttribute' => ['store_id', 'member_name'],
    'message'         => 'The combination of Store ID and Member Name has already been taken.'
]

[
    ['country_id'],
    'exist',
    'skipOnError'     => true,
    'targetClass'     => Country::className(),
    'targetAttribute' => ['country_id' => 'id'],
    'message'         => '此{attribute}不存在。'
]

[
    ['card_id', 'card_code'],
    //至少要一个
    function ($attribute, $param) {
        if (empty($this->card_code) && empty($this->card_id)) {
            $this->addError($attribute, 'card_id/card_code至少要填一个');
        }
    },
    'skipOnEmpty' => false
]

// SELECT * FROM `user` WHERE `name` LIKE 'php%'
$query = User::find()->where(['LIKE', 'name', 'php%', false]);

$id = Yii::$app->request->get('id');
$collection = Yii::$app->db->cache(function (Connection $db) use($id){
    return self::findOne(['id'=>$id]);
}, 10); // 缓存10秒
var_dump($collection);

$subQuery = new Query();
$subQuery->from(PostComment::tableName())->where(['status' => PostComment::STATUS_ACTIVE])
        ->orderBy(['created_at' => SORT_DESC]);

$this->module->id
$this->id
$this->action->id

echo array_values($model->getFirstErrors())[0];
exit;

public function actionDownload()
{
    // downUrl
    return \Yii::$app->response->setDownloadHeaders($model->downUrl);
}

\yii\helpers\VarDumper::dump($var);
// 第二个参数是数组的深度  第三个参数是是否显示代码高亮（默认不显示）
\yii\helpers\VarDumper::dump($var, 10 , true);

// 方法一
Yii::$app->runAction('new_controller/new_action', $params);
// 方法二
return (new SecondController('second', Yii::$app->module))->runAction('index', $data);

Yii::$app->getRequest->get('id');
// 效率更高
Yii::$app->getRequest()->get('id');

Yii::$app->controller->module->id;
Yii::$app->controller->id
Yii::$app->controller->action->id

// 可以原样显示<script></script>代码，但不解析
echo yii\helpers\Html::encode($view_hello_str)
// 可以过滤掉<script></script>代码
echo yii\helpers\HtmlPurifier::process($view_hello_str)

'user' => [
    'class'         => 'yii\web\User',
    'identityClass' => 'common\models\User',
    'loginUrl'      => ['/user/sign-in/login'],
    'authTimeout'   => 1800, // 登陆有效时间
    'as afterLogin' => 'common\behaviors\LoginTimestampBehavior'
],

$config['modules']['debug'] = [
    'class'      => 'yii\debug\Module',
    'allowedIPs' => ['127.0.0.1', '192.168.0.*', '192.168.33.1'],
];