模型状态有效，但返回状态 400

>我试图弄清楚我的路由发生了什么。下面是控制器中具有两条路由的操作。

public enum AvaibleScheduleEventParticipantGroupType
{
    Teachers,
    ...
}
[HttpGet]
[Route("groups/{type}/{id?}", Order = 1)]
[Route("groups/{type}", Order = 2)]
[ResponseType(typeof(IEnumerable))]
public IEnumerable GetParticipantGroupForScheduleEvent(AvaibleScheduleEventParticipantGroupType type, Guid? id = null)
{
    var request = new ScheduleEventParticipantGroupRequest
    {
        Type = type,
        Id = id
    };
    return GettingParticipantGroupForScheduleEventService.HandleGroupRequest(request);
}

在

花了一些时间玩弄路由路径后，我终于找到了一个解决方案，当我尝试导航时，它不会以消息"在控制器上找不到操作"

结束

http://localhost:65358/api/scheduleevents/groups/teachers

现在我变得400 status了，我没有对我的参数进行验证。奇怪。我用Output窗口查看了 IIS 中发生的事情，发现这个：

w3wp.exe Information: 0 : Request, Method=GET, Url=http://localhost:65358/api/scheduleevents/groups/teachers, Message='http://localhost:65358/api/scheduleevents/groups/teachers'
w3wp.exe Information: 0 : Message='ScheduleEvent', Operation=DefaultHttpControllerSelector.SelectController
w3wp.exe Information: 0 : Message='Nau.Dzienniczek.Api.Areas.Schedule.Controllers.ScheduleEventController', Operation=DefaultHttpControllerActivator.Create
w3wp.exe Information: 0 : Message='Nau.Dzienniczek.Api.Areas.Schedule.Controllers.ScheduleEventController', Operation=HttpControllerDescriptor.CreateController
w3wp.exe Information: 0 : Message='Selected action 'GetParticipantGroupForScheduleEvent(AvaibleScheduleEventParticipantGroupType type, Nullable`1 id)'', Operation=ApiControllerActionSelector.SelectAction
w3wp.exe Information: 0 : Operation=AuthorizeAttribute.OnAuthorizationAsync
w3wp.exe Information: 0 : Message='Parameter 'type' bound to the value 'Teachers'', Operation=ModelBinderParameterBinding.ExecuteBindingAsync
w3wp.exe Information: 0 : Message='Parameter 'id' bound to the value 'null'', Operation=ModelBinderParameterBinding.ExecuteBindingAsync
w3wp.exe Information: 0 : Message='Model state is valid. Values: type=Teachers, id=null', Operation=HttpActionBinding.ExecuteBindingAsync
w3wp.exe Information: 0 : Operation=ValidateModelAttribute.OnActionExecutingAsync, Status=400 (BadRequest)
w3wp.exe Information: 0 : Operation=ScheduleEventController.ExecuteAsync, Status=400 (BadRequest)
w3wp.exe Information: 0 : Operation=DependencyScopeHandler.SendAsync, Status=400 (BadRequest)
w3wp.exe Information: 0 : Response, Status=400 (BadRequest), Method=GET, Url=http://localhost:65358/api/scheduleevents/groups/teachers, Message='Content-type='none', content-length=unknown'
w3wp.exe Information: 0 : Operation=ScheduleEventController.Dispose

仔细观察底部的第 6 行。

'Model state is valid. Values: type=Teachers, id=null'

其次是

Operation=ValidateModelAttribute.OnActionExecutingAsync, Status=400 (BadRequest)

这到底是怎么回事呢？

下面的网址就像一个魅力。

http://localhost:65358/api/scheduleevents/groups/teachers/1e7cb4f9-8e6a-4127-9505-5fad9978ebc6

[HttpGet, Route("api/scheduleevents/groups/{type}/{id:guid?}")]
public IHttpActionResult GetParticipantGroupForScheduleEvent(string type, Guid? id = null)
{
    try
    {
       var request = new ScheduleEventParticipantGroupRequest
       {
           Type = type,
           Id = id
       };
      //assuming this returns an object or list of objects
       var response = GettingParticipantGroupForScheduleEventService.HandleGroupRequest(request);
       return Ok(response);
    }
    catch
    {
       return InternalServerError();
    }
}