How to avoid MVC resetting ExceptionContext.Result? - angularjs

Question

I am using the following code to handle exceptions in my MVC controllers:
protected override void OnException(ExceptionContext filterContext)
{
if (filterContext.HttpContext.Request.Headers["X-Requested-With"] == "XMLHttpRequest")
{
filterContext.Result = new JsonResult
{
JsonRequestBehavior = JsonRequestBehavior.AllowGet,
Data = new { Error = true, Msj = filterContext.Exception.Message }
};
}
}
In the front-end I am using angularjs ($http) to execute the requests.
If I set filterContext.ExceptionHandled to true, $http will execute the successCallback function but if I don't set it, .Net will reset the filterContext.Result to the tipycal yellow page.
I want to manage the error with the errorCallback function($http) but avoid .Net resetting the Data property of the JsonResult
Does anyone have any idea how to achieve it?
Any help will be appreciated =D

Answer 1

Angular $http service does not send the X-Requested-With headers by default. You need to explicitly enable it.
var app = angular.module('yourApp', []);
app.config(['$httpProvider', function ($httpProvider) {
$httpProvider.defaults.headers.common["X-Requested-With"] = 'XMLHttpRequest';
}]);
EDIT : As per the comment
The problem is that .Net replaces the 'Data' property
Because your are missing 2 things in your OnException method.
You need to set the ExceptionHandled property to true so that the framework will not do the normal exception handling procedure and return the default yellow screen of death page.
You need to specify the Response status code as 5xx ( Error response). The client library will determine whether to execute the success callback or error callback based on the status code on the response coming back.
The below code should totally work.
protected override void OnException(ExceptionContext filterContext)
{
if (filterContext.HttpContext.Request.Headers["X-Requested-With"] == "XMLHttpRequest")
{
filterContext.Result = new JsonResult
{
JsonRequestBehavior = JsonRequestBehavior.AllowGet,
Data = new { Error = true, Msj = filterContext.Exception.Message }
};
filterContext.HttpContext.Response.StatusCode = 500;
filterContext.ExceptionHandled = true;
}
}