C# WebApi 全局配置模型验证和自定义错误处理。config Filters Add ModelStateValidationFilter/CustomExceptionFilter

public static void Start()
{
logger.Debug("Startup WebAPI...");
SwaggerConfig.Register();

GlobalConfiguration.Configure(WebApiConfig.Register);

。。。

 public static class WebApiConfig
    {

        public static void Register(HttpConfiguration config)
        {
            config.MapHttpAttributeRoutes();

            config.Filters.Add(new CustomExceptionFilterAttribute());
            config.Filters.Add(new ModelStateValidationFilterAttribute());
        }
    }

　　

CustomExceptionFilterAttribute :

using System;
using System.Linq;
using System.Net.Http;
using System.Web.Http;
using System.Web.Http.Filters;
using GlobalPaymentsPortalWebApi.Exceptions;
using NLog;

namespace TestWebApi.Filters
{
    public class CustomExceptionFilterAttribute : ExceptionFilterAttribute
    {
        readonly ILogger logger = LogManager.GetCurrentClassLogger();

        public override void OnException(HttpActionExecutedContext actionExecutedContext)
        {
            var requestInfo = actionExecutedContext.Request.Method.Method + " " + actionExecutedContext.Request.RequestUri.PathAndQuery;
            if (actionExecutedContext.Exception is CustomException customException)
            {
                var res = new CustomErrorResponse(((CustomException)actionExecutedContext.Exception).Code, ((CustomException)actionExecutedContext.Exception).Error);
                HttpResponseMessage httpResponse = new HttpResponseMessage(System.Net.HttpStatusCode.BadRequest);
                httpResponse.Content = new ObjectContent<CustomErrorResponse>(res, GlobalConfiguration.Configuration.Formatters.JsonFormatter);
                actionExecutedContext.Response = httpResponse;

                string modelErrors = string.Empty;
                if (!actionExecutedContext.ActionContext.ModelState.IsValid)
                {
                    modelErrors = actionExecutedContext.ActionContext.ModelState.SelectMany(state => state.Value.Errors).Aggregate("", (current, error) => current + (error.ErrorMessage + "  "));
                }

                if (!string.IsNullOrEmpty(customException.Error))
                {
                    logger.Info("{0}: {1} -> [{2}]: {3}", customException.Code, customException.Error, requestInfo, modelErrors);
                }
                else
                {
                    logger.Info("{0} -> [{1}]: {2}", customException.Code, requestInfo, modelErrors);
                }
            }
            else if (actionExecutedContext.Exception is NotFoundException notfoundException)
            {
                actionExecutedContext.Response = new HttpResponseMessage(System.Net.HttpStatusCode.NotFound);
                logger.Info("NotFound -> [{0}]", requestInfo);
            }
            else
            {
                actionExecutedContext.Response = new HttpResponseMessage(System.Net.HttpStatusCode.InternalServerError);
                logger.Error(actionExecutedContext.Exception, "{0} -> [{1}]", actionExecutedContext.Exception.Message, requestInfo);
            }
        }
    }
}

　　

ModelStateValidationFilterAttribute :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web.Http.Controllers;
using System.Web.Http.Filters;

namespace TestWebApi.Filters
{
    public class ModelStateValidationFilterAttribute : ActionFilterAttribute
    {
        public override void OnActionExecuting(HttpActionContext actionContext)
        {
            if(!actionContext.ModelState.IsValid)
            {
                throw new CustomException(CustomError.BadRequestParameter);
            }

            base.OnActionExecuting(actionContext);
        }
    }
}

　　

CustomException :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.Text;
using System.Threading.Tasks;

namespace TestWebApi.Exceptions
{
    public enum CustomError
    {
        Unknown = 0,
        BadRequestParameter,
        DuplicatedKey,
        LoginFailed,
        DuplicatedLoyaltyTier,
        DuplicatedKioskType,
        CancelFailed,
        DeployFailed
    }

    [Serializable]
    public class CustomException : Exception
    {
        public CustomError Code { get; }

        public string Error { get; }

        public CustomException(CustomError code, string error = null)
        {
            Code = code;
            Error = error;
        }

    }
}

　　

 public class CustomErrorResponse
    {
        [Required]
        public CustomError? Code { get; set; }

        public string Error { get; set; }
        public CustomErrorResponse(CustomError code, string error = null)
        {
            Code = code;
            Error = error;
        }
    }