public static void RegisterRoutes(RouteCollection routes)
{ routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.MapRoute( name: "Default", url: "{controller}/{action}/{id}", defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional } );
}//1、当请求/Home/Index/1时，路由系统把最后一个片段1赋值给id变量。//2、Action Invoker通过路由信息得知当前请求需要Index这个Action来处理；//3、Action Invoker通过Model Binder（模型绑定器）来创建调用Action方法需要的数据对象；//4、最后Action Invoker将数据对象赋值给Index这个Action的参数，再调用这个Action完成Http请求。

namespace System.Web.Mvc
{ public interface IModelBinder { object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext); }
}

public ActionResult DisplayAddress([Bind(Prefix="HomeAddress")]Address address)
{return View(address);
}

public ActionResult Address()
{IList<Address> addresses = new List<Address>();UpdateModel(addresses, new FormValueProvider(ControllerContext));return View(addresses);
}

//用 Action 方法的某个集合类型的参数来指定并存储从某一个来源获取的数据，这个集合类型(示例的 FormCollection) 也是 IValueProvider 接口的一个实现。public ActionResult Address(FormCollection formData)
{IList<Address> addresses = new List<Address>();UpdateModel(addresses, formData);return View(addresses);
}

public ActionResult Address(FormCollection formData)
{IList<Address> addresses = new List<Address>();try {UpdateModel(addresses, formData);}catch (InvalidOperationException ex) {var allErrors = ModelState.Values.SelectMany(v => v.Errors);// do something with allErrors and provide feedback to user
    }return View(addresses);
}

//1、实现IValueProvier接口
public class CountryValueProvider : IValueProvider
{public bool ContainsPrefix(string prefix){return prefix.ToLower().IndexOf("country") > -1;}public ValueProviderResult GetValue(string key) {if (ContainsPrefix(key))return new ValueProviderResult("China", "China", CultureInfo.InvariantCulture);elsereturn null;}
}//2、自定义ValueProviderFactory来实例化自定义的ValueProvider
public class CustomValueProviderFactory : ValueProviderFactory
{public override IValueProvider GetValueProvider(ControllerContext controllerContext) {return new CountryValueProvider();}
}//3、在Global类的Applcation_Start方法中进行注册
protected void Application_Start()
{AreaRegistration.RegisterAllAreas();//通过 ValueProviderFactories.Factories 静态集合的 Insert 方法注册了我们的 CustomValueProviderFactory 类。    //Insert 方法中的 0 参数保证 Binder 将首先使用自定义的类来提供值。    //如果我们想在其他 value provider 不能提供值的时候使用，那么我们可以使用 Add 方法：ValueProviderFactories.Factories.Add(new CustomValueProviderFactory());ValueProviderFactories.Factories.Insert(0, new CustomValueProviderFactory());
}

//1、实现IModelBinder接口
public class AddressBinder : IModelBinder
{public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) {Address model = (Address)bindingContext.Model ?? new Address();model.City = GetValue(bindingContext, "City");model.Country = GetValue(bindingContext, "Country");return model;}private string GetValue(ModelBindingContext context, string name) {name = (context.ModelName == "" ? "" : context.ModelName + ".") + name;ValueProviderResult result = context.ValueProvider.GetValue(name);if (result == null || result.AttemptedValue == "") return "<Not Specified>";else return (string)result.AttemptedValue;}
}//2、注册
protected void Application_Start()
{AreaRegistration.RegisterAllAreas();ModelBinders.Binders.Add(typeof(Address), new AddressBinder());
}