子对象上的ASP.NET MVC 2模型验证(DataAnnotations)

两句话:

• 您尝试验证的实例需要通过modelbinder才能工作

我认为第一句话不需要太多解释:

public class Filter
{
    [StringLength(5)]
    public String Text { get; set; }
}

public class MainObject
{
    public Filter Filter { get; set; }
}

至于第二个,当它不起作用时:

public ActionResult Index()
{
    // Here the instantiation of the model didn't go through the model binder
    MainObject mo = GoFetchMainObjectSomewhere();
    bool isValid = TryValidateModel(mo); // This will always be true
    return View();
}

它什么时候起作用:

public ActionResult Index(MainObject mo)
{
    bool isValid = TryValidateModel(mo);
    return View();
}

public ActionResult Index(MainObject mo)
{
    bool isValid = ModelState.IsValid;
    return View();
}

结论:你很少需要 TryValidateModel