如何在knockout.js中获取单选按钮上的值和标签？

<input type="radio" name="gender" value="male" data-bind="checked: selectedGender" /> Male
<input type="radio" name="gender" value="female" data-bind="checked: selectedGender" /> Female

function ViewModel() {
    var self = this;
    self.selectedGender = ko.observable('male'); // 默认选中male
}

console.log(viewModel.selectedGender()); // 输出选中的值，例如'male'