How to add code for MesageBoxButton

I want my form submit when I click MessageBoxButton OK and if I click Cancel button my form not be submitted and when my form submit, text box radio button and other control  will initialize and text box will be blank. Please help to right code.
such as
 private void btnSubmit_Click(object sender, EventArgs e)
{
MessageBox.Show("Prese ok for submit data....","Information ! Check Data and pres ok for submited other wise pres cancel button for Cancellation......... ",MessageBoxButtonOKCancel, MessageBoxButtonIcon.Information);

//and then..........what we write
}