Application_Error in global.asax 未捕获 WebAPI 中的错误

Question

对于我正在从事的一个项目，我们正在实施的其中一件事是我们在我的一些团队中有一些较早的 ASP.NET 和 MVC 项目的代码——一个 Application_Error 例外向开发团队发送电子邮件的捕手，其中包含异常体验和最相关的详细信息。

外观如下：

Global.asax:

protected void Application_Error(object sender, EventArgs e)
{
    Exception ex = Server.GetLastError();
    string path = "N/A";
    if (sender is HttpApplication)
        path = ((HttpApplication) sender).Request.Url.PathAndQuery;

    string args = string.Format("<b>Path:</b> {0}", path);

    // Custom code that generates an HTML-formatted exception dump
    string message = Email.GenerateExceptionMessage(ex, args);

    // Custom code that sends an email to the dev team.
    Email.SendUnexpectedErrorMessage("Some App", message);
}

但是有一个 "minor" 问题 - 当我故意让一部分代码抛出异常以测试此机制时...

public static void GetMuffinsByTopping(string topping)
{
    throw new Exception("Test Exception!", new Exception("Test Inner Exception!!!"));

    // Actual repository code is unreachable while this test code is there
}

前端JavaScript立即拦截了一个HTTP 500请求，但是没有到达上面提到的global.asax.cs代码（我在方法的第一行执行设置了一个断点。 )

问题： 怎样才能让"old" Application_Error handler派发错误邮件，让我们团队的开发者更容易调试我们的申请？

Answer 1

将您的错误处理逻辑从 Application_Error 抽象到它自己的函数中。创建一个 Web API exception filter.

//register your filter with Web API pipeline
//this belongs in the Application_Start event in Global Application Handler class (global.asax)
//or some other location that runs on startup
GlobalConfiguration.Configuration.Filters.Add(new LogExceptionFilterAttribute());

//Create filter
public class LogExceptionFilterAttribute : ExceptionFilterAttribute 
{
    public override void OnException(HttpActionExecutedContext context)
    {
        ErrorLogService.LogError(context.Exception);
    }
}

//in global.asax or global.asax.cs
protected void Application_Error(object sender, EventArgs e)
{
    Exception ex = Server.GetLastError();
    ErrorLogService.LogError(ex);
} 

//common service to be used for logging errors
public static class ErrorLogService
{
    public static void LogError(Exception ex)
    {
        //Email developers, call fire department, log to database etc.
    }
}

来自 Web API 的错误不会触发 Application_Error 事件。但是我们可以创建一个异常过滤器并注册它来处理错误。另见 Global Error Handling in ASP.NET Web API 2.

Answer 2

就我而言，我不想使用 Web.config。然后我在 Global.asax 文件中创建了上面的代码：

protected void Application_Error(object sender, EventArgs e)
    {
        Exception ex = Server.GetLastError();

        //Not Found (When user digit unexisting url)
        if(ex is HttpException && ((HttpException)ex).GetHttpCode() == 404)
        {
            HttpContextWrapper contextWrapper = new HttpContextWrapper(this.Context);

            RouteData routeData = new RouteData();
            routeData.Values.Add("controller", "Error");
            routeData.Values.Add("action", "NotFound");

            IController controller = new ErrorController();
            RequestContext requestContext = new RequestContext(contextWrapper, routeData);
            controller.Execute(requestContext);
            Response.End();
        }
        else //Unhandled Errors from aplication
        {
            ErrorLogService.LogError(ex);
            HttpContextWrapper contextWrapper = new HttpContextWrapper(this.Context);

            RouteData routeData = new RouteData();
            routeData.Values.Add("controller", "Error");
            routeData.Values.Add("action", "Index");

            IController controller = new ErrorController();
            RequestContext requestContext = new RequestContext(contextWrapper, routeData);
            controller.Execute(requestContext);
            Response.End();
        }
    }

那是我的 ErrorController.cs

public class ErrorController : Controller
{
    // GET: Error
    public ViewResult Index()
    {
        Response.StatusCode = 500;
        Exception ex = Server.GetLastError();
        return View("~/Views/Shared/SAAS/Error.cshtml", ex);
    }

    public ViewResult NotFound()
    {
        Response.StatusCode = 404;
        return View("~/Views/Shared/SAAS/NotFound.cshtml");
    }
}

这是我从@mason class

复制的ErrorLogService.cs

//common service to be used for logging errors
public static class ErrorLogService
{
    public static void LogError(Exception ex)
    {
        //Do what you want here, save log in database, send email to police station
    }
}

Application_Error in global.asax 未捕获 WebAPI 中的错误

Application_Error in global.asax not catching errors in WebAPI

c#

asp.net

.net

asp.net-web-api

error-reporting