My app: VS2010, MVC3, C#, latest ELMAH
Case: some errors happens (e.g. null reference), custom error page is shown (customErrors mode="On").
Task: allow admins (users in role Admins, ) view error detail from custom error page
Question: How to obtain/pass elmah error id to the custom error page view ?
Upd: Related answered question: ELMAH - Using custom error pages to collecting user feedback
Custom error page sample:
#model System.Web.Mvc.HandleErrorInfo
#{
ViewBag.Title = "Error";
}
<h2>
Error processing a request.
#if (User.IsInRole(MyAppNamespace.Constants.ROLE_ADMIN))
{
// where to obtain ELMAH error id to navigate to error details ?
// elmah/detail?id=291f5e83-5756-43bf-a889-07a548727da7
View error details
}
</h2>
It is an event in Elmah ErrorLog module, that can be handled in Global.asax.cs:
protected void ErrorLog_Logged(object sender, ErrorLoggedEventArgs args)
{
Session["ElmahId"] = args.Entry.Id;
}
Then we can use stored id to navigate to error (I am using Elmah.Mvc module that implements special controller instead of default elmah pages). In Error.cshtml:
#if (User.IsInRole(renweb.Constants.ROLE_ADMIN))
{
Error details
}
From what I know all Elmah errors are saved in a table called EMAH_Error.
So one thing you could do is to get the current date time when the error occurred and query the table for the records saved on that time give/take 1 minute. The query it will return the error saved with the appropriate time stamp that will also contain the ErrorId.
You can easily use EF or something else to create and entity ElmahError.
Related
I am following a guide to integrate PayPal into MVC 4. However, I have come upon this error "The name "Session" does not exist in the current context." & "The name "Response" does not exist in the current context."
https://www.asp.net/web-forms/overview/getting-started/getting-started-with-aspnet-45-web-forms/checkout-and-payment-with-paypal
protected void CheckoutBtn_Click(object sender, ImageClickEventArgs e)
{
using (ShoppingCart usersShoppingCart = new ShoppingCart())
{
Session["payment_amt"] = usersShoppingCart.GetTotal();
}
Response.Redirect("Checkout/CheckoutStart.aspx");
}
}
I have inputted the above code in my model which is linked to the checkout page.
Please enlighten me thanks. I am new to MVC.
It sounds like you're missing the System.Web namespace. Include it at the top of your class like so. If you then receive an error to the tune of 'namespace cannot be found', then you're missing the reference to System.Web.
I am new to ASP.NET MVC , Kendo UI (razor) , Jquery. I have an application that throws 3 kinds of errors
Unhanded exceptions (400, 403,500 503 etc) - throw generic exceptions
Expected exceptions/ errors (custom exceptions) - e.g. Trying to create a contact that already exist in the system - The system needs to throw "Contact_duplicated_exception" and show this to the user as "Contact was previously created. This action could not proceed".
Model state errors (UI). Errors that I add to modelstate to showup on the page using #Html.ValidationSummary(true)
What is the best standard way of handling the above throughout the application ?
I need to send these messages back to the user using Jquery Ajax [POST].
I have used the following concepts but I need to implement a standard way of dealing with the above
1. I have used ELMAH (for unhanded exceptions)
2. Application_Error(object sender, EventArgs e) in global.asax.cs
3. Custom HandleErrorArrtibute
public class HandleErrorWithAjaxFilter : HandleErrorAttribute, IExceptionFilter
Thanks!
For #1 and #3, you're looking good, IMHO. However, I think your weak-point is #2 and here is why:
If the exception is expected it should not be allowed to fall to Application_Error; because, well... it's expected, it's workflow, not an exception.
Therefore as a reaction to user input and part of workflow, it should be handled as part of #3.
So, in your shoes, I would go about in the specific instance of finding duplicates adding a validation attribute onto the potentially duplicate class like so:
[AttributeUsage(AttributeTargets.Class)]
public class UniqueContactAttribute : ValidationAttribute
{
public override bool IsValid(object value)
{
bool isValid = true;
Contact contact = value as Contact;
if(contact != null)
{
// check for your duplicate in the database and set isValid to false if you find one.
}
return isValid;
}
}
Usage for your metadata class:
[UniqueContact(ErrorMessage = "Contact was previously created. This action could not proceed.")]
public class Contact_Validation
{
}
I have mvc 3 application which when a Standard generic throw new Exception is thrown in code the error page from Views\Shared\error.cshtml is shown. This is done by simply setting <customErrors mode="On"/>. (This is As expected and as Desired)
The application is using WCF services in middle tier which when these services generate FaultException MVC is not showing up the error page it is showing details of the web service call to the user on screen. All I want to do is handle the error in my code and show the user the Error.cshtml. I have tried changing global asax but this dosent work.
protected void Application_Error(object sender, EventArgs e)
{
Exception exception = Server.GetLastError();
if (exception.GetType() == typeof(FaultException))
{
throw new Exception("There was a fault exception that i do not want to show details of to user.");
}
}
Try creating an ErrorController as asp.net MVC will try to resolve the link you specified in the web.config as {Controller}/{View} unless you specify it to ignore that page. Also, you may want to apply an attribute to handle exceptions instead.
You can also create a error controller/view and in your catch block redirect to the custom error page of your choosing
try
{
foo.bar()
}
catch(SpecificException)
{
RedirectToAction("500", "Error");
}
Is there a built in or a proper way to handle errors in asp.net mvc 3?
This is what I want to do:
If the application crashes, or throws an error, it goes to a specific error page.
I can throw my own error from the controller action. (and it goes to an error page).
I found the following ways:
I see there is a long way to do it
here. (for v1 and v2 but also
applies to v3).
Using errorhandle attribute here.
How do I handle this the proper way?
If the solution is similar or is like #1 in the list above, I am using ninject and I have not created a base class. How do I still do this?
For Global Error Handling
All you have to do is change the customErrors mode="On" in web.config page
Error will be displayed through Error.cshtml resides in shared folder.
Make sure that Error.cshtml Layout is not null.
[It sould be something like: #{ Layout = "~/Views/Shared/_Layout.cshtml"; }
Or remove Layout=null code block]
A sample markup for Error.cshtml:-
#{ Layout = "~/Views/Shared/_Layout.cshtml"; }
#model System.Web.Mvc.HandleErrorInfo
<!DOCTYPE html>
<html>
<head>
<title>Error</title>
</head>
<body>
<h2>
Sorry, an error occurred while processing your request.
</h2>
<p>Controller Name: #Model.ControllerName</p>
<p>Action Name : #Model.ActionName</p>
<p>Message: #Model.Exception.Message</p>
</body>
</html>
For Specific Error Handling
Add HandleError attribute to specific action in controller class. Provide 'View' and 'ExceptionType' for that specific error.
A sample NotImplemented Exception Handler:
public class MyController: Controller
{
[HandleError(View = "NotImplErrorView", ExceptionType=typeof(NotImplementedException))]
public ActionResult Index()
{
throw new NotImplementedException("This method is not implemented.");
return View();
}
}
I would suggest implementing a custom HandleErrorAttribute action filter.
See this link for more details:
http://msdn.microsoft.com/en-us/library/dd410203%28v=vs.90%29.aspx
Setting up a HandleErrorAttribute action filter gives you complete control over which actions are handled by the filter, and it's easy to set at the controller level, or even at the site level by setting it up on a custom base controller, and having all of your controllers inherit from the base controller.
Something else I do with this, is I have a separate HandleJsonErrorAttribute that responds to Ajax calls by returning a Json response, rather than the custom page.
UPDATE:
Per some questions below, here is an example of a HandleJsonErrorAttribute that I use:
public class HandleJsonErrorAttribute : HandleErrorAttribute
{
public override void OnException(ExceptionContext filterContext)
{
var serviceException = filterContext.Exception as ServiceException;
filterContext.HttpContext.Response.StatusCode = (int)HttpStatusCode.InternalServerError;
filterContext.Result = new JsonResult { Data = new { message = serviceException == null ? "There was a problem with that request." : serviceException.Message } };
filterContext.ExceptionHandled = true;
}
}
And here is the jQuery that I use to handle these unhanded exceptions:
$(document).ajaxError(function (event, jqXHR, ajaxSettings, thrownError) {
showPopdown($.parseJSON(jqXHR.responseText).message);
});
This allows my Ajax methods to be very lightweight -- they just handle returning normal Json, and in the event of an unhanded exception, a message w/ an error status code gets wrapped in Json and returned.
Also, in my implementation, I have a custom ServiceException that I throw from services, and this sends the message from the service layer instead of a generic message.
The easiest way I think you can do that is using the elmah library.
Take a look at this: http://code.google.com/p/elmah/wiki/MVC and this
http://www.hanselman.com/blog/ELMAHErrorLoggingModulesAndHandlersForASPNETAndMVCToo.aspx
I think the easiest way is using ExceptionHandler attribute since it's ready to use anytime you create a new ASP.NET MVC 3 project. You can still configure Web.config to use a custom error page and handling exceptions in global Application_Error method as usual but when an exception occurs the URL is not displayed as nice as the new MVC 3's way.
you can create custom exception in MVC if you want to customize a way of exception handling.
you can find useful post here .
http://www.professionals-helpdesk.com/2012/07/creating-custom-exception-filter-in-mvc.html
All I need would be just the error message in plain text. But ASP.NET is doing some HTML report output from every error.
I have a jquery ajax call and when an error is thrown I'm getting all that crap over to the client side.
I've created a filter attribute but didn't helped.
public class ClientErrorHandler : FilterAttribute, IExceptionFilter
{
public void OnException(ExceptionContext filterContext)
{
var responce = filterContext.RequestContext.HttpContext.Response;
responce.Write(filterContext.Exception.Message);
responce.ContentType = MediaTypeNames.Text.Plain;
filterContext.ExceptionHandled = true;
}
}
EDIT
I'm seeing this
and I'd like to see just what is in here filterContext.Exception.Message
It looks to me like the reason why you cannot correctly handle the exception is because it happens outside of the MVC pipeline. If you look at the stack trace in the code you posted there is no reference to System.Web.Mvc code (the firing of exception filters when an exception occurs is called from ControllerActionInvoker.InvokeAction).
The stack trace indicates that the exception happens late in the ASP.NET pipeline (OnEndRequest) and that it's coming through the Autofac component.
To capture this error you would have to subscribe to the HttpApplication's Error event. See the following article on creating a global error handler: http://msdn.microsoft.com/en-us/library/994a1482.aspx . In this event you can handle the error and redirect to a custom error page.
you need to return a ContentResult
ContentResult result = new ContentResult();
result.Content = filterContext.Exception.Message;
result.ContentType = MediaTypeNames.Text.Plain;
filterContext.Result = result;
filterContext.ExceptionHandled = true;
Since you're using JQuery and WCF (by the details of your error), you might want to take a look at this article on how to handle service faults elegantly between jQuery and WCF - you might have to rework your service if you are able to do so.