protected function splitHeader($header)
    {
        list($name, $value) = explode(':', $header, 2);
        
        return [trim($name), trim($value), strtolower(trim($name))];
    }
protected function splitHeader($header)
    {
        list($name, $value) = explode(':', $header, 2);
        
        return [trim($name), trim($value), strtolower(trim($name))];
    }
protected function splitHeader ( $ header ) { list ( $ name , $ value ) = explode ( ':' , $ header , 2 ) ; return [ trim ( $ name ) , trim ( $ value ) , strtolower ( trim ( $ name ) ) ] ; }
Split a header string in name and value

@param string $header
@return array [name, value, key]
Split a header string in name and value