src/Cache/Request/FileCache.php
function isValid()
    {
        $cacheFile = $this->cachePath . $this->cacheKey;
        if (!file_exists($cacheFile)) {
            return false;
        }

        if ((time() - filemtime($cacheFile)) < $this->expireTime) {
            return true;
        }

        return false;
    }
function isValid()
    {
        $cacheFile = $this->cachePath . $this->cacheKey;
        if (!file_exists($cacheFile)) {
            return false;
        }

        if ((time() - filemtime($cacheFile)) < $this->expireTime) {
            return true;
        }

        return false;
    }
是否有效

@return bool