How to redirect to another Action / Controller in MVC3 from VOID method?

Question

I have a controller method that returns void because it creates an Excel report for user to download. The third-party Excel library that we use records the response itself. The method looks something like this:

[HttpGet] public void GetExcel(int id) { try { var report = _reportService.GetReport(id); var table = _reportService.GetReportTable(id); var excelReport = new ExcelReport(table, report.Name); excelReport.DownloadReport(System.Web.HttpContext.Current.Response); } catch (Exception ex) { // This is wrong, of course, because I'm not returning an ActionResult Response.RedirectToRoute("/Report/Error/", new { exceptionType = ex.GetType().Name }); } } 

There are several security checks that throw exceptions if the user does not meet certain credentials to receive the report. I want to redirect to another page and pass some exception information, but I cannot figure out how to do this in MVC3 ....

Any ideas?

Answer 1

You can do

 Response.Redirect(Url.Action("Error", "Report", new { exceptionType = ex.GetType().Name }); 

But did you take a look at FilePathResult or FileStreamResult ?

Answer 2

Instead of letting the 3rd part library write the answer directly, use the usual ActionResult to get the contents and return File(...) for the actual file or RedirectToAction(...) (or RedirectToRoute(...) ) if an error occurs. If your third-party library can only write in Response, you may need to use some tricks to output it.

 [HttpGet] public ActionResult GetExcel(int id) { try { var report = _reportService.GetReport(id); var table = _reportService.GetReportTable(id); var excelReport = new ExcelReport(table, report.Name); var content = excelReport.MakeReport(System.Web.HttpContext.Current.Response); return File(content, "application/xls", "something.xls"); } catch (Exception ex) { RedirectToRoute("/Report/Error/", new { exceptionType = ex.GetType().Name }); } } 

Answer 3

You can return EmptyActionResult :

 [HttpGet] public ActionResult GetExcel(int id) { try { var report = _reportService.GetReport(id); var table = _reportService.GetReportTable(id); var excelReport = new ExcelReport(table, report.Name); excelReport.DownloadReport(System.Web.HttpContext.Current.Response); return new EmptyResult(); } catch (Exception ex) { return RedirectToAction("Error", "Report", rnew { exceptionType = ex.GetType().Name }); } } 

Not sure if it works, have not tested it.

Answer 4

Another approach would be to use an exception filter:

 public class MyExceptionFilter : FilterAttribute, IExceptionFilter { public void OnException(ExceptionContext filterContext) { var routeValues = new RouteValueDictionary() { { "controller", "Error" }, { "action", "Report" } }; filterContext.Result = new RedirectToRouteResult(routeValues); filterContext.ExceptionHandled = true; // Or I can skip the redirection and render a whole new view //filterContext.Result = new ViewResult() //{ // ViewName = "Error" // //.. //}; } }