Yii 2.0如何使用页面缓存方法示例

一、前言

二、示例代码

```php

namespace mon\lib;

use Yii;

use yii\caching\Cache;

use yii\di\Instance;

use yii\web\Response;

use yii\filters\PageCache as PCache;

class PageCache extends PCache {

// 参数设置，默认无参数，用法'varByParam' => Yii::$app->request->get('id')

public $varByParam = '';

public function beforeAction($action) {

if (!$this->enabled) {

return true;

}

$this->cache = Instance::ensure($this->cache, Cache::className());

if (is_array($this->dependency)) {

$this->dependency = Yii::createObject($this->dependency);

}

$properties = [];

foreach(['cache', 'duration', 'dependency', 'variations'] as $name) {

$properties[$name] = $this->$name;

}

// 根据路由和参数生成缓存ID

$id = $this->varyByRoute ? $action->getUniqueId() . $this->varByParam : __CLASS__;

$response = Yii::$app->getResponse();

ob_start(); // 开启输出缓冲

ob_implicit_flush(false); // 关闭隐式刷新

if ($this->view->beginCache($id, $properties)) { // 开始缓存视图输出

$response->on(Response::EVENT_AFTER_SEND, [$this, 'cacheResponse']); // 监听响应事件，进行缓存操作

return true; // 成功开始缓存视图输出，返回true