public class HttpGlobalExceptionFilter : IExceptionFilter
  {
    public void OnException(ExceptionContext context)
    {
      throw new NotImplementedException();
    }
  }

  /// <summary>
  /// 全局異常過濾器
  /// </summary>
  public class HttpGlobalExceptionFilter : IExceptionFilter
  {
    readonly ILoggerFactory _loggerFactory;
    readonly IHostingEnvironment _env;

    public HttpGlobalExceptionFilter(ILoggerFactory loggerFactory, IHostingEnvironment env)
    {
      _loggerFactory = loggerFactory;
      _env = env;
    }

    public void OnException(ExceptionContext context)
    {
      var logger = _loggerFactory.CreateLogger(context.Exception.TargetSite.ReflectedType);

        logger.LogError(new EventId(context.Exception.HResult),
        context.Exception,
        context.Exception.Message);

        var json = new ErrorResponse("未知錯誤,請重試");

        if (_env.IsDevelopment()) json.DeveloperMessage = context.Exception;

        context.Result = new ApplicationErrorResult(json);
        context.HttpContext.Response.StatusCode = (int)HttpStatusCode.InternalServerError;

      context.ExceptionHandled = true;
    }

public class ApplicationErrorResult : ObjectResult
  {
    public ApplicationErrorResult(object value) : base(value)
    {
      StatusCode = (int)HttpStatusCode.InternalServerError;
    }
  }

public class ErrorResponse
  {
    public ErrorResponse(string msg)
    {
      Message = msg;
    }
    public string Message { get; set; }
    public object DeveloperMessage { get; set; }
  }

services.AddMvc(options =>
      {
        options.Filters.Add<HttpGlobalExceptionFilter>();
      });