asp.net-mvc Action filters Exception Handler Attribute
Example
This attribute handles all unhandled exceptions in the code, (this is mostly for Ajax Requests - that deal with JSON - but can be extended)
public class ExceptionHandlerAttribute : HandleErrorAttribute
{
/// <summary>
/// Overriden method to handle exception
/// </summary>
/// <param name="filterContext"> </param>
public override void OnException(ExceptionContext filterContext)
{
// If exeption is handled - return ( don't do anything)
if (filterContext.ExceptionHandled)
return;
// Set the ExceptionHandled to true ( as you are handling it here)
filterContext.ExceptionHandled = true;
//TODO: You can Log exception to database or Log File
//Set your result structure
filterContext.Result = new JsonResult
{
Data = new { Success = false, Message = filterContext .Exception.Message, data = new {} },
JsonRequestBehavior = JsonRequestBehavior.AllowGet
};
}
}
So let's say you always have to send a JSON response similar to this:
{
Success: true, // False when Error
data: {},
Message:"Success" // Error Message when Error
}
So instead of handling exceptions in controller actions, like this:
public ActionResult PerformMyAction()
{
try
{
var myData = new { myValue = 1};
throw new Exception("Handled", new Exception("This is an Handled Exception"));
return Json(new {Success = true, data = myData, Message = ""});
}
catch(Exception ex)
{
return Json(new {Success = false, data = null, Message = ex.Message});
}
}
You can do this:
[ExceptionHandler]
public ActionResult PerformMyAction()
{
var myData = new { myValue = 1};
throw new Exception("Unhandled", new Exception("This is an unhandled Exception"));
return Json(new {Success = true, data = myData, Message = ""});
}
OR you can add at Controller level
[ExceptionHandler]
public class MyTestController : Controller
{
public ActionResult PerformMyAction()
{
var myData = new { myValue = 1};
throw new Exception("Unhandled", new Exception("This is an unhandled Exception"));
return Json(new {Success = true, data = myData, Message = ""});
}
}
