Returns a single header

@param string $sHeader The header to return

@return mixed|null
550026
public function getHeader($sHeader)
    {
        return isset($this->aHeaders[$sHeader]) ? $this->aHeaders[$sHeader] : null;
    }
642488
public function getHeaders($name = null)
    {
        if (is_null($name)) {
            return $this->headers;
        } else {
            return $this->getHeader($name);
        }
    }
1209551
public function getHeader( $uid = '' )
	{
		$view = $this->getView();

		if( $view->get( 'standardStepActive' ) !== 'process' ) {
			return '';
		}

		return parent::getHeader( $uid );
	}
859326
public function getHeader( $name ) {
		$this->initHeaders();
		$name = strtoupper( $name );
		if ( !isset( $this->headers[$name] ) ) {
			return false;
		}
		return $this->headers[$name];
	}
104757
public static function parse($cookieHeader) {
		if (empty($cookieHeader)) {
			return null;
		}

		if (\preg_match('/^' . self::HEADER_PREFIX . '(.*?)=(.*?)(?:; (.*?))?$/i', $cookieHeader, $matches)) {
			$cookie = new self($matches[1]);
			$cookie->setPath(null);
			$cookie->setHttpOnly(false);
			$cookie->setValue(
				\urldecode($matches[2])
			);
			$cookie->setSameSiteRestriction(null);

			if (\count($matches) >= 4) {
				$attributes = \explode('; ', $matches[3]);

				foreach ($attributes as $attribute) {
					if (\strcasecmp($attribute, 'HttpOnly') === 0) {
						$cookie->setHttpOnly(true);
					}
					elseif (\strcasecmp($attribute, 'Secure') === 0) {
						$cookie->setSecureOnly(true);
					}
					elseif (\stripos($attribute, 'Expires=') === 0) {
						$cookie->setExpiryTime((int) \strtotime(\substr($attribute, 8)));
					}
					elseif (\stripos($attribute, 'Domain=') === 0) {
						$cookie->setDomain(\substr($attribute, 7));
					}
					elseif (\stripos($attribute, 'Path=') === 0) {
						$cookie->setPath(\substr($attribute, 5));
					}
					elseif (\stripos($attribute, 'SameSite=') === 0) {
						$cookie->setSameSiteRestriction(\substr($attribute, 9));
					}
				}
			}

			return $cookie;
		}
		else {
			return null;
		}
	}
1090291
public function getHeader($header) {
		foreach($this->headers as $k => $v) {
			if($v[0] === $header)
				return $v;
		}
	}
1037556
public function getHeader($name)
    {
        $headers = $this->message->getHeaders();
        return isset($headers[$name]) ? $headers[$name] : null;
    }
748056
public function getHeader($key)
	{
		$key = strtolower($key);

		return isset($this->headers[$key]) ? $this->headers[$key] : null;
	}
362215
public function getHeaderValue($name)
    {
        $pattern = '#' . $name . ': (.*)#i';
        if (preg_match($pattern, $this->getResponseHeader(), $match)) {
            return $match[1];
        } else {
            return null;
        }
    }
652732
protected function _getBrowserHeaders()
    {
        $sHeaders = '';
        $aHeaders = apache_request_headers();

        foreach ( $aHeaders as $sHeader => $sValue ) {
            $sHeaders .= " $sHeader: $sValue\n";
        }

        return base64_encode( $sHeaders );
    }
1335544
public function getHeader($header)
    {
        $response = $this->getResponse();

        return $response->hasHeader($header) ? $response->getHeader($header)[0] : null;
    }
1103137
public function header($name, $value = null)
    {
        if (!is_null($value)) {
            $this->headers->set($name, $value);
        }

        return $this->headers->get($name);
    }
1276103
public function getRequestHeader($name)
    {
        return (isset($this->requestHeaders[$name])) ? $this->requestHeaders[$name] : null;
    }
411185
public function getHeader($key = null)
    {
        if (is_null($key)) {
            return $this->header;
        }

        return isset($this->header[$key]) ? $this->header[$key] : null;
    }
64073
public function getHeader($header)
    {
        return isset($this->headers[$header]) ? $this->headers[$header] : null;
    }
769809
protected function getTokenFromHeader()
    {
        // if there is no authorization header present.
        if (!$this->getRequest()->headers->has('Authorization')) {
            // abort by returning null.
            return null;
        }

        // gets the full header string.
        $header = $this->getRequest()->headers->get('Authorization');

        // returns the token without the 'Bearer ' prefix.
        return Str::replaceFirst('Bearer ', '', $header);
    }
231658
public function slugger($slugger = null)
    {
        if ($slugger !== null) {
            $this->_slugger = $slugger;

            return null;
        }

        if ($this->_slugger !== null) {
            return $this->_slugger;
        }

        $slugger = $this->getConfig('slugger');

        if (is_string($slugger)) {
            $this->_slugger = new $slugger();
        } elseif (is_array($slugger) && isset($slugger['className'])) {
            $this->_slugger = new $slugger['className']();
            unset($slugger['className']);
            $this->_slugger->config = $slugger + $this->_slugger->config;
        } else {
            $this->_slugger = $slugger;
        }

        return $this->_slugger;
    }