using radio button checkbox to be checked true in DGV

Note it is windows application. Design as follows; i have one radio button. two check boxes inside the data grid view in my design page. Run Mode screen as follows; One Radio Button In data grid view as follows; Checkbox1 Checkbox2. I want when i click the radio button, checkbox1 and checkbox2 all the rows in the datagridview will be checked true. for that how can i do? in the radio button checked change event what code i have to written.