Yii2.0使用数据库

准备好数据库：

新建一个数据库yii2basic，然后在其中创建一张表：

CREATE TABLE `country` (
    `code` CHAR(2) NOT NULL PRIMARY KEY,
    `name` CHAR(52) NOT NULL,
    `population` INT(11) NOT NULL DEFAULT '0'
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO `country` VALUES ('AU','Australia',18886000);
INSERT INTO `country` VALUES ('BR','Brazil',170115000);
INSERT INTO `country` VALUES ('CA','Canada',1147000);
INSERT INTO `country` VALUES ('CN','China',1277558000);
INSERT INTO `country` VALUES ('DE','Germany',82164700);
INSERT INTO `country` VALUES ('FR','France',59225700);
INSERT INTO `country` VALUES ('GB','United Kingdom',59623400);
INSERT INTO `country` VALUES ('IN','India',1013662000);
INSERT INTO `country` VALUES ('RU','Russia',146934000);
INSERT INTO `country` VALUES ('US','United States',278357000);

配置数据库连接：

在config/db.php中：

<?php
return [
    'class' => 'yii\db\Connection',
    'dsn' => 'mysql:host=localhost;dbname=yii2basic',
    'username' => 'root',
    'password' => '',
    'charset' => 'utf8',
];

创建一个ActiveRecord：

models/Country.php：

<?php
    namespace app\models;
    use yii\db\ActiveRecord;
    class Country extends ActiveRecord
    {
    }

创建一个Action：

controllers/CountryController.php：

<?php
    namespace app\controllers;
    use yii\web\Controller;
    use yii\data\Pagination;
    use app\models\Country;
    class CountryController extends Controller
    {
        public function actionIndex()
        {
            $query = Country::find();
            $pagination = new Pagination([
                'defaultPageSize' => 5,
                'totalCount' => $query->count(),
            ]);
        $countries = $query->orderBy('name')
            ->offset($pagination->offset)
            ->limit($pagination->limit)
            ->all();
        return $this->render('index', [
            'countries' => $countries,
            'pagination' => $pagination,
        ]);
    }
}

创建视图

view/country/index.php：

<?php
    use yii\helpers\Html;
    use yii\widgets\LinkPager;
?>
<h1>Countries</h1>
<ul>
<?php foreach ($countries as $country): ?>
   <li>
       <?= Html::encode("{$country->name} ({$country->code})") ?>:
       <?= $country->population ?>
   </li>
<?php endforeach; ?>
</ul>

<?= LinkPager::widget(['pagination' => $pagination]) ?>

试试吧：

http://hostname/index.php?r=country/index