作为对先前答案的补充。

昨天，ASP.NET Web API 2.1正式发布
它提供了另一个在全球范围内处理异常的机会
样本中给出了详细信息。

简单地说，您可以添加全局异常记录器和/或全局异常处理程序(仅一个(
您将它们添加到配置中：

public static void Register(HttpConfiguration config)
{
  config.MapHttpAttributeRoutes();
  // There can be multiple exception loggers.
  // (By default, no exception loggers are registered.)
  config.Services.Add(typeof(IExceptionLogger), new ElmahExceptionLogger());
  // There must be exactly one exception handler.
  // (There is a default one that may be replaced.)
  config.Services.Replace(typeof(IExceptionHandler), new GenericTextExceptionHandler());
}

以及他们的实现：

public class ElmahExceptionLogger : ExceptionLogger
{
  public override void Log(ExceptionLoggerContext context)
  {
    ...
  }
}
public class GenericTextExceptionHandler : ExceptionHandler
{
  public override void Handle(ExceptionHandlerContext context)
  {
    context.Result = new InternalServerErrorTextPlainResult(
      "An unhandled exception occurred; check the log for more information.",
      Encoding.UTF8,
      context.Request);
  }
}

如果web API托管在ASP.NET应用程序中，则将为代码中的所有未处理异常调用Application_Error事件，包括所显示的测试操作中的异常。因此，您所要做的就是在Application_Error事件中处理此异常。在您展示的示例代码中，您只处理类型为HttpException的异常，这显然不是Convert.ToInt32("a")代码的情况。因此，请确保您在其中记录并处理所有异常：

protected void Application_Error()
{
    Exception unhandledException = Server.GetLastError();
    HttpException httpException = unhandledException as HttpException;
    if (httpException == null)
    {
        Exception innerException = unhandledException.InnerException;
        httpException = innerException as HttpException;
    }
    if (httpException != null)
    {
        int httpCode = httpException.GetHttpCode();
        switch (httpCode)
        {
            case (int)HttpStatusCode.Unauthorized:
                Response.Redirect("/Http/Error401");
                break;
            // TODO: don't forget that here you have many other status codes to test 
            // and handle in addition to 401.
        }
        else
        {
            // It was not an HttpException. This will be executed for your test action.
            // Here you should log and handle this case. Use the unhandledException instance here
        }
    }
}

Web API中的异常处理可以在不同级别进行。这里有一个detailed article解释了不同的可能性：

• 可以注册为全局异常筛选器的自定义异常筛选器属性

  [AttributeUsage(AttributeTargets.All)]
  public class ExceptionHandlingAttribute : ExceptionFilterAttribute
  {
      public override void OnException(HttpActionExecutedContext context)
      {
          if (context.Exception is BusinessException)
          {
              throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)
              {
                  Content = new StringContent(context.Exception.Message),
                  ReasonPhrase = "Exception"
              });
          }
          //Log Critical errors
          Debug.WriteLine(context.Exception);
          throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)
          {
              Content = new StringContent("An error occurred, please try again or contact the administrator."),
              ReasonPhrase = "Critical Exception"
          });
      }
  }
  

• 自定义操作调用程序

  public class MyApiControllerActionInvoker : ApiControllerActionInvoker
  {
      public override Task<HttpResponseMessage> InvokeActionAsync(HttpActionContext actionContext, System.Threading.CancellationToken cancellationToken)
      {
          var result = base.InvokeActionAsync(actionContext, cancellationToken);
          if (result.Exception != null && result.Exception.GetBaseException() != null)
          {
              var baseException = result.Exception.GetBaseException();
              if (baseException is BusinessException)
              {
                  return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError)
                  {
                      Content = new StringContent(baseException.Message),
                      ReasonPhrase = "Error"
                  });
              }
              else
              {
                  //Log critical error
                  Debug.WriteLine(baseException);
                  return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError)
                  {
                      Content = new StringContent(baseException.Message),
                      ReasonPhrase = "Critical Error"
                  });
              }
          }
          return result;
      }
  }
  

为什么要重新考虑etc？这是有效的，它将使服务返回状态500等

public class LogExceptionFilter : ExceptionFilterAttribute
{
    private static readonly ILog log = LogManager.GetLogger(typeof (LogExceptionFilter));
    public override void OnException(HttpActionExecutedContext actionExecutedContext)
    {
        log.Error("Unhandeled Exception", actionExecutedContext.Exception);
        base.OnException(actionExecutedContext);
    }
}

你有没有想过做一些像这样的处理错误操作过滤器

[HandleError]
public class BaseController : Controller {...}

您还可以创建[HandleError]的自定义版本，使用该版本可以将错误信息和所有其他详细信息写入日志

将整个过程封装在try/catch中，并记录未处理的异常，然后将其传递。除非有更好的内置方法。

以下是一个参考CatchAll(已处理或未处理(异常

(编辑：哦，API(