朋友问到一个问题，如何输出自定义错误页面，不使用302跳转。当前页面地址不能改变.
还要执行一些代码等,生成一些错误信息,方便用户提交反馈.
500错误，mvc框架已经有现成解决方法：
filters.Add(new HandleErrorAttribute());
404错误目前想到的解决方法：
先上代码 Global.asax：
1 protected void Application_Error(object sender, EventArgs e) 2 { 3 var ex = Server.GetLastError() as HttpException; 4 if (ex == null) 5 return; 6 7 var httpStatusCode = ex.GetHttpCode(); 8 9 if (httpStatusCode == 404)10 {11 var httpContext = (sender as MvcApplication).Context;12 13 httpContext.ClearError();14 httpContext.Response.Clear();15 httpContext.Response.StatusCode = 404;16 ServiceFocus.LogService.AddLog(ex);17 18 httpContext.Response.ContentType = "text/html; charset=utf-8";19 var routeData = new RouteData();20 routeData.Values["controller"] = "Sys";21 routeData.Values["action"] = "NotFound";22 var requestContext = new RequestContext(new HttpContextWrapper(httpContext), routeData);23 var controller = ControllerBuilder.Current.GetControllerFactory().CreateController(requestContext, "Sys") as SysController;24 //controller.ViewData.Model=model;25 (controller as IController).Execute(requestContext);26 ControllerBuilder.Current.GetControllerFactory().ReleaseController(controller);27 }
controller代码：
1 public class CompressAttribute : ActionFilterAttribute 2 { 3 public override void OnActionExecuting(ActionExecutingContext filterContext) 4 { 5 var acceptEncoding = filterContext.HttpContext.Request.Headers["Accept-Encoding"]; 6 if (!string.IsNullOrEmpty(acceptEncoding)) 7 { 8 acceptEncoding = acceptEncoding.ToLower(); 9 var response = filterContext.HttpContext.Response;10 if (acceptEncoding.Contains("gzip"))11 {12 response.AppendHeader("Content-encoding", "gzip");13 response.Filter = new GZipStream(response.Filter, CompressionMode.Compress);14 }15 else if (acceptEncoding.Contains("deflate"))16 {17 response.AppendHeader("Content-encoding", "deflate");18 response.Filter = new DeflateStream(response.Filter, CompressionMode.Compress);19 }20 }21 }22 }23 [Compress]24 public class SysController : Controller25 {26 //27 // GET: /sys/28 29 public ActionResult NotFound()30 {31 return View();32 }33 public ActionResult Error()34 {35 return View();36 }37 }
web.config
启用输出错误信息，否则iss在外网请求的时候不会看到自定义的输出的错误信息
目前有几个疑惑，没有深究：还望有网友知道能解惑一二，就不用去google 扒源码了。
1.如果不加这行代码，默认输出的是：text/html; 浏览器直接输出内容,不做解析.
httpContext.Response.ContentType = "text/html; charset=utf-8";
2.iis不会使用gzip压缩,不管输出的404错误页面有多大,都不会自动压缩.所以使用下面这种替换方式.
[Compress] public class SysController : Controller
猜测:
mvc 在action的Execute阶段后 还做了不少事情,比如上面提到的1,2点.正常200请求会执行默认的filter等阶段.
而当是404请求时,跳过了这些阶段.可能500请求也类似.
仅仅是猜测,还未验证,
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