route attribute in webapi

安装：Install-Package Microsoft.AspNet.WebApi.WebHost

引用：System.Web.Http.HttpConfigurationExtensions

配置：

webapi2

public static class WebApiConfig
{
    public static void Register(HttpConfiguration config)
    {
        // Attribute routing.
        config.MapHttpAttributeRoutes();

        // Convention-based routing.
        config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );
    }
}

webapi1

protected void Application_Start()
{
    // WARNING - Not compatible with attribute routing.
    //WebApiConfig.Register(GlobalConfiguration.Configuration);
      GlobalConfiguration.Configure(WebApiConfig.Register);
}

使用：

public class OrdersController : ApiController
{
    [Route("customers/{customerId}/orders")]
    [HttpGet]
    public IEnumerable<Order> FindOrdersByCustomer(int customerId) { ... }
}

tips

• {}中的变量名和方法参数名匹配
• 没有设置Route属性的方法使用默认路由
• [AcceptVerbs("MKCOL")] 可以指定非标准谓词
• RoutePrefix
  

  [RoutePrefix("api/books")]
  public class BooksController : ApiController
  {
      // GET api/books
      [Route("")]
      public IEnumerable<Book> Get() { ... }
  
      // GET api/books/5
      [Route("{id:int}")]
      public Book Get(int id) { ... }
  
      // POST api/books
      [Route("")]
      public HttpResponseMessage Post(Book book) { ... }
  
      // GET /api/authors/1/books
      [Route("~/api/authors/{authorId:int}/books")]
      public IEnumerable<Book> GetByAuthor(int authorId) { ... }
  }

• 约束参数
  

  [Route("users/{id:int:min(1)}")]
  public User GetUserById(int id) { ... }
  //{x:regex(^d{3}-d{3}-d{4}$)}
  //{x:range(10,50)}
  //{x:alpha}

  自定义约束
  

  //定义
  public class NonZeroConstraint : IHttpRouteConstraint
  {
      public bool Match(HttpRequestMessage request, IHttpRoute route, string parameterName, 
          IDictionary<string, object> values, HttpRouteDirection routeDirection)
      {
          object value;
          if (values.TryGetValue(parameterName, out value) && value != null)
          {
              long longValue;
              if (value is long)
              {
                  longValue = (long)value;
                  return longValue != 0;
              }
  
              string valueString = Convert.ToString(value, CultureInfo.InvariantCulture);
              if (Int64.TryParse(valueString, NumberStyles.Integer, 
                  CultureInfo.InvariantCulture, out longValue))
              {
                  return longValue != 0;
              }
          }
          return false;
      }
  }
  //注册
  public static class WebApiConfig
  {
      public static void Register(HttpConfiguration config)
      {
          var constraintResolver = new DefaultInlineConstraintResolver();
          constraintResolver.ConstraintMap.Add("nonzero", typeof(NonZeroConstraint));
  
          config.MapHttpAttributeRoutes(constraintResolver);
      }
  }
  //使用
  [Route("{id:nonzero}")]
  public HttpResponseMessage GetNonZero(int id) { ... }

• 可选参数和默认值
  

  public class BooksController : ApiController
  {
      [Route("api/books/locale/{lcid:int?}")]
      public IEnumerable<Book> GetBooksByLocale(int lcid = 1033) { ... }
  }
  
  
  public class BooksController : ApiController
  {
      [Route("api/books/locale/{lcid:int=1033}")]
      public IEnumerable<Book> GetBooksByLocale(int lcid) { ... }
  }

• Routs name
  

  public class BooksController : ApiController
  {
      [Route("api/books/{id}", Name="GetBookById")]
      public BookDto GetBook(int id) 
      {
          // Implementation not shown...
      }
  
      [Route("api/books")]
      public HttpResponseMessage Post(Book book)
      {
          // Validate and add book to database (not shown)
  
          var response = Request.CreateResponse(HttpStatusCode.Created);
  
          // Generate a link to the new book and set the Location header in the response.
          string uri = Url.Link("GetBookById", new { id = book.BookId });
          response.Headers.Location = new Uri(uri);
          return response;
      }
  }

• RouteOrder
  解析路由的顺序，默认order是0,越小越先，越精确越先
  

  [RoutePrefix("orders")]
  public class OrdersController : ApiController
  {
      [Route("{id:int}")] // constrained parameter
      public HttpResponseMessage Get(int id) { ... }
  
      [Route("details")]  // literal
      public HttpResponseMessage GetDetails() { ... }
  
      [Route("pending", RouteOrder = 1)]
      public HttpResponseMessage GetPending() { ... }
  
      [Route("{customerName}")]  // unconstrained parameter
      public HttpResponseMessage GetByCustomer(string customerName) { ... }
  
      [Route("{*date:datetime}")]  // wildcard
      public HttpResponseMessage Get(DateTime date) { ... }
  }
  
  //order
  orders/details
  orders/{id}
  orders/{customerName}
  orders/{*date}
  orders/pending

link:http://www.asp.net/web-api/overview/web-api-routing-and-actions/attribute-routing-in-web-api-2