@param string $key

@return string|null
357501
private function getNestedValueByKey($key)
    {
        if (isset($this->nestedKeyCache[$key])) {
            return $this->nestedKeyCache[$key];
        }

        // Check to see if this is targeting an instance of ArrayContainer and grab it from the nested container
        $keyParts = explode('.', $key);
        if ($this->get($keyParts[0]) instanceof self && $arrayContainer = $this->get($keyParts[0])) {
            array_shift($keyParts);
            /* @var ArrayContainer $arrayContainer */
            $value = $arrayContainer->get(implode('.', $keyParts));
        } else {
            $value = $this->items;
            foreach (explode('.', $key) as $keyPart) {
                if ((! is_array($value) || ! $value instanceof self)) {
                    if (is_object($value) && method_exists($value, 'arrayAccessByKey')) {
                        if ($value = $value->arrayAccessByKey($keyPart)) {
                            break;
                        } else {
                            return null;
                        }
                    }
                }

                if (! isset($value[$keyPart])) {
                    return null;
                }

                if (is_array($value[$keyPart]) && ! array_key_exists($keyPart, $value)) {
                    return null;
                }
                $value = $value[$keyPart];
            }
        }

        $this->nestedKeyCache[$key] = $value;

        return $value;
    }
376063
public function offsetGet( $key )
    {
        $key = strtolower( $key );
        if ( !array_key_exists( $key, $this->lookup ) )
        {
            return null;
        }
        return $this->map[$this->lookup[$key]];
    }
1217474
public function getParamByKey($key)
    {
        if (isset($this->extParams[$key]))
        {
            return $this->extParams[$key];
        }

        return null;
    }
558643
public function get(string $key)
    {
        if (array_key_exists($key, $this->get)) {
            return $this->get[$key];
        }

        return '';
    }
748056
public function getHeader($key)
	{
		$key = strtolower($key);

		return isset($this->headers[$key]) ? $this->headers[$key] : null;
	}
519744
protected function retrieve($key)
    {
        if (($cache = wincache_ucache_get($this->key . $key)) !== false) {
            return $cache;
        }

        return null;
    }
602358
public function getParam($key)
    {
        return isset($this->params[$key]) ? $this->params[$key] : null;
    }
745276
public static function get(string $key)
    {
        if (isset($_COOKIE[$key]) === false) {
            return null;
        }

        $serializedValue = $_COOKIE[$key];
        $value = unserialize($serializedValue);

        return $value;
    }
1203566
protected function constructKey(?string $key = null) : ?string
    {
        if (!is_null($key) && !is_null($this->current)) {
            return $this->current.'.'.$key;
        }

        if (is_null($key) && !is_null($this->current)) {
            return $this->current;
        }

        return $key;
    }
1345319
protected function get($key)
    {
        $this->checkForNonEmptyKey($key);
        if (!$this->requestDataHasBeenRetrieved) {
            $this->retrieveRequestData();
        }
        if (!isset($this->cachedRequestData[$key])) {
            return null;
        }

        return $this->cachedRequestData[$key];
    }
518754
public function get($key) {
        $filename = $this->generateFileLocation($key);
        if (file_exists($filename) && is_readable($filename)) {
            $cache = unserialize(file_get_contents($filename));
            if ($cache['expires'] > time()) {
                return $cache['content'];
            } else {
                unlink($filename);
            }
        }
        return null;
    }
766029
private function getProperty($key)
    {
        return array_key_exists($key, $this->fields) ? $this->fields[$key] : null;
    }
1126558
public function get($key)
	{
		$key = strtolower($key);
		if (isset($this->summoners[$key]))
		{
			return $this->summoners[$key];
		}

		return null;
	}
969519
public function get($key)
	{
		if ( ! isset($this->strings[$key]))
		{
			return null;
		}

		return $this->strings[$key];
	}
966751
protected function getValuesFromKeyMap( $key )
    {
        if ( empty( $key ) || empty( $this->keyMap[$key] ) )
        {
            return null;
        }

        return $this->keyMap[$key];
    }
356350
public function getValue($key)
    {
        return isset($this->langstrings[$key]) ? $this->langstrings[$key] : null;
    }
655638
protected function retrieve($key)
    {
        if (array_key_exists($key, $this->storage)) {
            return $this->storage[$key];
        }

        return null;
    }