CheckBox previousCheckBox = null;
private void chkPerson_Click(object sender, RoutedEventArgs e)
{
if(previousCheckBox!=null)
{
previousCheckBox.IsChecked = false;
}
CheckBox currentCheckBox = sender as CheckBox;
previousCheckBox = currentCheckBox;
}
private void chkPerson_Unchecked(object sender, RoutedEventArgs e)
{
previousCheckBox = null;
}