获取缓存内容
@param string $name 缓存名称
@return null|mixed
502693
public static function getCache($name)
    {
        if (is_callable(self::$cache_callable['get'])) {
            return call_user_func_array(self::$cache_callable['get'], func_get_args());
        }
        $file = self::_getCacheName($name);
        if (file_exists($file) && ($content = file_get_contents($file))) {
            $data = unserialize($content);
            if (isset($data['expired']) && (intval($data['expired']) === 0 || intval($data['expired']) >= time())) {
                return $data['value'];
            }
            self::delCache($name);
        }
        return null;
    }
395104
public function get(string $name): ?string
    {
        return $this->dataContainer[RequestDataContainer::VAR_HEADER_RAW][$name] ?? null;
    }
53052
protected function getField($name)
    {
        $name = ltrim($name, '/');

        foreach ($this->fields as $field) {
            if (preg_match('#^' . ltrim($field->getName(), '/') . '$#', $name)) {
                return $field;
            }
        }

        return null;
    }
814496
public function getParameter($name)
    {
        $name = (string)$name;
        return array_key_exists($name, $this->_params) ? $this->_params[$name] : null;
    }
33987
public function get($name) {
        N('cache_read',1);
        $value = $this->handler->get($this->options['prefix'].$name);
        $jsonData  = json_decode( $value, true );
        return ($jsonData === NULL) ? $value : $jsonData;	//检测是否为JSON数据 true 返回JSON解析数组, false返回源数据
    }
286451
public function get(string $name): ?string
    {
        $key = strtolower($name);
        if (!isset($this->headers[$key])) {
            return null;
        }

        return $this->headers[$key][1];
    }
908830
public function getField($name)
    {
        return (null !== $name && array_key_exists($name, $this->fields)) ? $this->fields[$name] : null;
    }
758647
public function getParameter($name): ?Parameter
    {
        /** @var Parameter $parameter */
        foreach ($this->parameters as $parameter) {
            if ($parameter->getKey() === $name) {
                return $parameter;
            }
        }

        return null;
    }
1187311
public function getContent($name)
    {
        return $this->getContents()->filter(function (Content $content) use ($name) {
            return $content->getArea()->getName() == $name;
        })->first();
    }
323753
public function param($name)
    {
        $params = $this->params();
        if (isset($params[$name])) {
            return $params[$name];
        } else {
            return null;
        }
    }
976699
public function get($name)
    {
        if (is_null($name) || empty($name))
        {
            return null;
        }

        $loweredKey = strtolower($name);

        if (array_key_exists($loweredKey, $this->keyMap) === false)
        {
            return null;
        }

        $originalKey = $this->keyMap[$loweredKey];

        return $this->headerMap[$originalKey];
    }
705452
public function getQueryParameter($name)
    {
        return isset($this->info['query'][$name]) ? $this->info['query'][$name] : null;
    }
884228
public function get_param($name) {
        if (array_key_exists($name, $this->params)) {
            return $this->params[$name];
        } else {
            return null;
        }
    }
1363871
public function get($name) {
        $query = $this->queryAll();
        return isset($query[$name]) ? $query[$name] : null;
    }
367742
public static function get(string $name): ?string
    {
        $data = Session::get($name, null, self::$namespace);
        if (is_array($data) && array_key_exists('token', $data)) {
            return $data['token'];
        }
        return null;
    }
334593
public function getEncodedHeader(string $name): ?string
    {
        $offset = \strlen($name) + 2; // colon + space

        if (!isset($this->headers[$name])) {
            return null;
        }

        if (\is_array($this->headers[$name])) {
            $s = '';
            foreach ($this->headers[$name] as $email => $mailer) {
                if ($mailer != null) { // intentionally ==
                    $s .= self::encodeHeader($mailer, $offset, true);
                    $email = " <$email>";
                }
                $s .= self::append($email . ',', $offset);
            }

            return \ltrim(\substr($s, 0, -1)); // last comma
        }

        if (\preg_match('#^(\S+; (?:file)?name=)"(.*)"\z#', $this->headers[$name], $m)) { // Content-Disposition
            $offset += \strlen($m[1]);

            return $m[1] . '"' . self::encodeHeader($m[2], $offset) . '"';

        }

        return \ltrim(self::encodeHeader($this->headers[$name], $offset));
    }
190938
public static function get($name = null)
    {
        if ($name === null) {
            $name = array_shift(array_keys(self::$containers));
        }
        return self::$containers[$name] ? self::$containers[$name] : null;
    }