return [
            'pageCache' => [
                'class' => 'yii\filters\PageCache',
                'only' => ['index'],
                'variations' => [
                    '/',
                    Yii::$app->request->isAjax,
                ],
                'enabled'=>true,
                'duration' => Yii::$app->params['pageCacheDuration'],
            ],
        ];

$this->cache = Instance::ensure($this->cache, 'yii\caching\CacheInterface');

use yii\filters\PageCache;

class PageCacheCtInfo extends PageCache
{
	这里是内部逻辑，不需要重写的方法可以不写。
	public $checkUser = true; //可以自定义变量
}

            'pageCacheInfo' => [
                'class' => 'common\components\PageCacheCtInfo',
                'only' => ['info'],
                'enabled'=>Yii::$app->params['pageCacheEnabled'],
                'variations' => [
                    'ct/'.Yii::$app->request->pathInfo,
                    Yii::$app->request->isAjax
                ],
                'duration' => Yii::$app->params['pageCacheInfo'],
                'checkUser' = false,
            ],

    /**
     * @return array the key used to cache response properties.
     * @since 2.0.3
     */
    protected function calculateCacheKey()
    {
        $key = [__CLASS__];
        if ($this->varyByRoute) {
            $key[] = Yii::$app->requestedRoute;
        }
        return array_merge($key, (array)$this->variations);
    }

['yii\filters\PageCache','','/‘,0]

['yii\filters\PageCach', 'xxx/info','xxx/xxx/3xxxx74.html',0 ]

    /**
     * Stores a value identified by a key in cache.
     * This is the implementation of the method declared in the parent class.
     *
     * @param string $key the key identifying the value to be cached
     * @param string $value the value to be cached. Other types (If you have disabled [[serializer]]) unable to get is
     * correct in [[getValue()]].
     * @param int $duration the number of seconds in which the cached value will expire. 0 means never expire.
     * @return bool true if the value is successfully stored into cache, false otherwise
     */
    protected function setValue($key, $value, $duration)
    {
        $this->gc();
        $cacheFile = $this->getCacheFile($key);
        if ($this->directoryLevel > 0) {
            @FileHelper::createDirectory(dirname($cacheFile), $this->dirMode, true);
        }
        // If ownership differs the touch call will fail, so we try to
        // rebuild the file from scratch by deleting it first
        // https://github.com/yiisoft/yii2/pull/16120
        if (is_file($cacheFile)  function_exists('posix_geteuid')  fileowner($cacheFile) !== posix_geteuid()) {
            @unlink($cacheFile);
        }
        if (@file_put_contents($cacheFile, $value, LOCK_EX) !== false) {
            if ($this->fileMode !== null) {
                @chmod($cacheFile, $this->fileMode);
            }
            if ($duration = 0) {
                $duration = 31536000; // 1 year
            }

            return @touch($cacheFile, $duration + time());
        }

        $error = error_get_last();
        Yii::warning("Unable to write cache file '{$cacheFile}': {$error['message']}", __METHOD__);
        return false;
    }

    /**
     * Removes expired cache files.
     * @param bool $force whether to enforce the garbage collection regardless of [[gcProbability]].
     * Defaults to false, meaning the actual deletion happens with the probability as specified by [[gcProbability]].
     * @param bool $expiredOnly whether to removed expired cache files only.
     * If false, all cache files under [[cachePath]] will be removed.
     */
    public function gc($force = false, $expiredOnly = true)
    {
        if ($force || mt_rand(0, 1000000)  $this->gcProbability) {
            $this->gcRecursive($this->cachePath, $expiredOnly);
        }
    }

Yii::$app->cache->gc(true);

'components' => ['cache' => [
    'class' => 'yii\caching\FileCache',
],],