public function field($name)
    {
        return isset($this->_properties['fields'][$name])?
            $this->_properties['fields'][$name]:null;
    }
public function field($name)
    {
        return isset($this->_properties['fields'][$name])?
            $this->_properties['fields'][$name]:null;
    }
public function field ( $ name ) { return isset ( $ this -> _properties [ 'fields' ] [ $ name ] ) ? $ this -> _properties [ 'fields' ] [ $ name ] : null ; }
return field alias
return field alias