Asp.net MVC P2 中无法正确获取 CheckBox值的bug的解决方案

 View:
<%=Html.CheckBox("IsBirthday","我是否过生日", item.IsBirthday)%>
Controller:

AUser user = new AUser();
BindingHelperExtensions.UpdateFrom(user, Request.Form);

Model:

public class AUser{
    public bool IsBirthday{get;set;}
}

这样会发生无法从View中获取到IsBirthday值的情况
查了许多MS只能以以下方法解决
Controller:

AUser user = new AUser();
BindingHelperExtensions.UpdateFrom(user, Request.Form);
user.IsBirthday= Request.Form["IsBirthday"]=="true";

View:
<%=Html.CheckBox("IsBirthday","我是否过生日","true", item.IsBirthday)%>