How to get text field value which is define in iframe in controller.

Hi All,

Below is my  code defined in xml view.

<html:iframe id="ifrm" width="300px" height="500px" src="https://www.flybuys.co.nz/points_balance_widget"  onload="getData" />

Could you please explain me 1) how we can get the input value say "6014" in controller.

                                            2) How we can call the "GO" Button event in controller.

Thanks,

Manju