public function getHeader($name)
    {
        assert(is_string($name));

        $name = strtolower($name);

        if (isset($this->_headers[$name])) {
            return $this->_headers[$name];
        }

        return null;
    }
public function getHeader($name)
    {
        assert(is_string($name));

        $name = strtolower($name);

        if (isset($this->_headers[$name])) {
            return $this->_headers[$name];
        }

        return null;
    }
public function getHeader ( $ name ) { assert ( is_string ( $ name ) ) ; $ name = strtolower ( $ name ) ; if ( isset ( $ this -> _headers [ $ name ] ) ) { return $ this -> _headers [ $ name ] ; } return null ; }
Return an individual HTTP headers of the response

@param string $name - name of header

@return string - header value, NULL if header wasn't set in response
Return an individual HTTP headers of the response