ASP.NET MVC和web api 同时支持简单和自定义约束，简单的约束看起来像：
routes.MapRoute("blog", "{year}/{month}/{day}",
new { controller = "blog", action = "index" },
new { year = @"\d{4}", month = @"\d{2}", day = @"\d{2}" });
只匹配‘temp/selsius‘ 和‘temp/fahrenheit‘俩种情况
[Route("temp/{scale:values(celsius|fahrenheit)}")]
只匹配‘temp/整数‘
[Route("temp/{id:int}]
约束实现
public class LocaleRouteConstraint : IRouteConstraint
{
public string Locale { get; private set; }
public LocaleRouteConstraint(string locale)
{
Locale = locale;
}
public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)
{
object value;
if (values.TryGetValue("locale", out value) && !string.IsNullOrWhiteSpace(value as string))
{
string locale = value as string;
if (isValid(locale))
{
return string.Equals(Locale, locale, StringComparison.OrdinalIgnoreCase);
}
}
return false;
}
private bool isValid(string locale)
{
string[] validOptions = "EN-US|EN-GB|FR-FR".Split(‘|‘) ;
return validOptions.Contains(locale.ToUpper());
}
}
增加自定义路由属性
public class LocaleRouteAttribute : RouteFactoryAttribute
{
public LocaleRouteAttribute(string template, string locale)
: base(template)
{
Locale = locale;
}
public string Locale
{
get;
private set;
}
public override RouteValueDictionary Constraints
{
get
{
var constraints = new RouteValueDictionary();
constraints.Add("locale", new LocaleRouteConstraint(Locale));
return constraints;
}
}
public override RouteValueDictionary Defaults
{
get
{
var defaults = new RouteValueDictionary();
defaults.Add("locale", "en-us");
return defaults;
}
}
}
MVC Controller 或 Action使用自定义的约束属性
using System.Web.Mvc;
namespace StarDotOne.Controllers
{
[LocaleRoute("hello/{locale}/{action=Index}", "EN-GB")]
public class ENGBHomeController : Controller
{
// GET: /hello/en-gb/
public ActionResult Index()
{
return Content("I am the EN-GB controller.");
}
}
}
另一个controller
using System.Web.Mvc;
namespace StarDotOne.Controllers
{
[LocaleRoute("hello/{locale}/{action=Index}", "FR-FR")]
public class FRFRHomeController : Controller
{
// GET: /hello/fr-fr/
public ActionResult Index()
{
return Content("Je suis le contrôleur FR-FR.");
}
}
}
‘/hello/en-gb‘ 将会匹配到ENGBHomeController
’/hello/fr-fr‘将会匹配到FRFRHomeController
应用场景可以自己定义。
原文：http://www.cnblogs.com/sgciviolence/p/5652772.html