ASP.NET MVC自定义错误处理Application_Error Global.asax？

Question

我有一些基本代码来确定我的MVC应用程序中的错误.目前在我的项目,我有一个名为控制器Error与操作方法HTTPError404(),HTTPError500()和General().它们都接受一个字符串参数error.使用或修改下面的代码.将数据传递给Error控制器进行处理的最佳/正确方法是什么？我想尽可能提供强大的解决方案.

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

    HttpException httpException = exception as HttpException;
    if (httpException != null)
    {
        RouteData routeData = new RouteData();
        routeData.Values.Add("controller", "Error");
        switch (httpException.GetHttpCode())
        {
            case 404:
                // page not found
                routeData.Values.Add("action", "HttpError404");
                break;
            case 500:
                // server error
                routeData.Values.Add("action", "HttpError500");
                break;
            default:
                routeData.Values.Add("action", "General");
                break;
        }
        routeData.Values.Add("error", exception);
        // clear error on server
        Server.ClearError();

        // at this point how to properly pass route data to error controller?
    }
}

Answer 1

您可以直接重定向到控制器/操作并通过查询字符串传递信息,而不是为此创建新路由.例如:

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

  HttpException httpException = exception as HttpException;

  if (httpException != null) {
    string action;

    switch (httpException.GetHttpCode()) {
      case 404:
        // page not found
        action = "HttpError404";
        break;
      case 500:
        // server error
        action = "HttpError500";
        break;
      default:
        action = "General";
        break;
      }

      // clear error on server
      Server.ClearError();

      Response.Redirect(String.Format("~/Error/{0}/?message={1}", action, exception.Message));
    }

然后你的控制器会收到你想要的任何东西

// GET: /Error/HttpError404
public ActionResult HttpError404(string message) {
   return View("SomeView", message);
}

你的方法有一些权衡.在这种错误处理中循环非常小心.另外一点是,由于您要通过asp.net管道来处理404,因此您将为所有这些命中创建一个会话对象.对于频繁使用的系统,这可能是一个问题(性能).

Answer 2

要回答最初的问题"如何正确地将routedata传递给错误控制器？":

IController errorController = new ErrorController();
errorController.Execute(new RequestContext(new HttpContextWrapper(Context), routeData));

然后在ErrorController类中,实现如下函数:

[AcceptVerbs(HttpVerbs.Get)]
public ViewResult Error(Exception exception)
{
    return View("Error", exception);
}

这会将异常推送到View中.视图页面应声明如下:

<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<System.Exception>" %>

以及显示错误的代码:

<% if(Model != null) { %>  <p><b>Detailed error:</b><br />  <span class="error"><%= Helpers.General.GetErrorMessage((Exception)Model, false) %></span></p> <% } %>

以下是从异常树收集所有异常消息的函数:

    public static string GetErrorMessage(Exception ex, bool includeStackTrace)
    {
        StringBuilder msg = new StringBuilder();
        BuildErrorMessage(ex, ref msg);
        if (includeStackTrace)
        {
            msg.Append("\n");
            msg.Append(ex.StackTrace);
        }
        return msg.ToString();
    }

    private static void BuildErrorMessage(Exception ex, ref StringBuilder msg)
    {
        if (ex != null)
        {
            msg.Append(ex.Message);
            msg.Append("\n");
            if (ex.InnerException != null)
            {
                BuildErrorMessage(ex.InnerException, ref msg);
            }
        }
    }

Answer 3

我以前想过在MVC应用程序中集中全局错误处理例程的想法很困难.我在ASP.NET论坛上有一篇文章.

它基本上处理global.asax中的所有应用程序错误,而不需要错误控制器,使用[HandlerError]属性进行装饰,或者摆弄customErrorsweb.config中的节点.

Answer 4

我找到了Lion_cl注意到的ajax问题的解决方案.

Global.asax中:

protected void Application_Error()
    {           
        if (HttpContext.Current.Request.IsAjaxRequest())
        {
            HttpContext ctx = HttpContext.Current;
            ctx.Response.Clear();
            RequestContext rc = ((MvcHandler)ctx.CurrentHandler).RequestContext;
            rc.RouteData.Values["action"] = "AjaxGlobalError";

            // TODO: distinguish between 404 and other errors if needed
            rc.RouteData.Values["newActionName"] = "WrongRequest";

            rc.RouteData.Values["controller"] = "ErrorPages";
            IControllerFactory factory = ControllerBuilder.Current.GetControllerFactory();
            IController controller = factory.CreateController(rc, "ErrorPages");
            controller.Execute(rc);
            ctx.Server.ClearError();
        }
    }

ErrorPagesController

public ActionResult AjaxGlobalError(string newActionName)
    {
        return new AjaxRedirectResult(Url.Action(newActionName), this.ControllerContext);
    }

AjaxRedirectResult

public class AjaxRedirectResult : RedirectResult
{
    public AjaxRedirectResult(string url, ControllerContext controllerContext)
        : base(url)
    {
        ExecuteResult(controllerContext);
    }

    public override void ExecuteResult(ControllerContext context)
    {
        if (context.RequestContext.HttpContext.Request.IsAjaxRequest())
        {
            JavaScriptResult result = new JavaScriptResult()
            {
                Script = "try{history.pushState(null,null,window.location.href);}catch(err){}window.location.replace('" + UrlHelper.GenerateContentUrl(this.Url, context.HttpContext) + "');"
            };

            result.ExecuteResult(context);
        }
        else
        {
            base.ExecuteResult(context);
        }
    }
}

AjaxRequestExtension

public static class AjaxRequestExtension
{
    public static bool IsAjaxRequest(this HttpRequest request)
    {
        return (request.Headers["X-Requested-With"] != null && request.Headers["X-Requested-With"] == "XMLHttpRequest");
    }
}

Answer 5

也许在MVC中处理错误的更好方法是将HandleError属性应用于控制器或操作,并更新Shared/Error.aspx文件以执行您想要的操作.该页面上的Model对象包括Exception属性以及ControllerName和ActionName.

Answer 6

这可能不是 MVC 的最佳方式（/sf/answers/662297051/）

以下是在 Application_Error 中呈现视图并将其写入 http 响应的方法。您不需要使用重定向。这将阻止对服务器的第二次请求，因此浏览器地址栏中的链接将保持不变。这可能是好是坏，这取决于您想要什么。

Global.asax.cs

protected void Application_Error()
{
    var exception = Server.GetLastError();
    // TODO do whatever you want with exception, such as logging, set errorMessage, etc.
    var errorMessage = "SOME FRIENDLY MESSAGE";

    // TODO: UPDATE BELOW FOUR PARAMETERS ACCORDING TO YOUR ERROR HANDLING ACTION
    var errorArea = "AREA";
    var errorController = "CONTROLLER";
    var errorAction = "ACTION";
    var pathToViewFile = $"~/Areas/{errorArea}/Views/{errorController}/{errorAction}.cshtml"; // THIS SHOULD BE THE PATH IN FILESYSTEM RELATIVE TO WHERE YOUR CSPROJ FILE IS!

    var requestControllerName = Convert.ToString(HttpContext.Current.Request.RequestContext?.RouteData?.Values["controller"]);
    var requestActionName = Convert.ToString(HttpContext.Current.Request.RequestContext?.RouteData?.Values["action"]);

    var controller = new BaseController(); // REPLACE THIS WITH YOUR BASE CONTROLLER CLASS
    var routeData = new RouteData { DataTokens = { { "area", errorArea } }, Values = { { "controller", errorController }, {"action", errorAction} } };
    var controllerContext = new ControllerContext(new HttpContextWrapper(HttpContext.Current), routeData, controller);
    controller.ControllerContext = controllerContext;

    var sw = new StringWriter();
    var razorView = new RazorView(controller.ControllerContext, pathToViewFile, "", false, null);
    var model = new ViewDataDictionary(new HandleErrorInfo(exception, requestControllerName, requestActionName));
    var viewContext = new ViewContext(controller.ControllerContext, razorView, model, new TempDataDictionary(), sw);
    viewContext.ViewBag.ErrorMessage = errorMessage;
    //TODO: add to ViewBag what you need
    razorView.Render(viewContext, sw);
    HttpContext.Current.Response.Write(sw);
    Server.ClearError();
    HttpContext.Current.Response.End(); // No more processing needed (ex: by default controller/action routing), flush the response out and raise EndRequest event.
}

看法

@model HandleErrorInfo
@{
    ViewBag.Title = "Error";
    // TODO: SET YOUR LAYOUT
}
<div class="">
    ViewBag.ErrorMessage
</div>
@if(Model != null && HttpContext.Current.IsDebuggingEnabled)
{
    <div class="" style="background:khaki">
        <p>
            <b>Exception:</b> @Model.Exception.Message <br/>
            <b>Controller:</b> @Model.ControllerName <br/>
            <b>Action:</b> @Model.ActionName <br/>
        </p>
        <div>
            <pre>
                @Model.Exception.StackTrace
            </pre>
        </div>
    </div>
}

Answer 7

Application_Error 有 Ajax 请求的问题。如果在 Ajax 调用的 Action 中处理错误 - 它将在结果容器中显示您的错误视图。