Asp.net MVC ModelState.Clear

by

I think is a bug in MVC. I struggled with this issue for hours today.

Given this:

public ViewResult SomeAction(SomeModel model) 
{
    model.SomeString = "some value";
    return View(model); 
}

The view renders with the original model, ignoring the changes. So I thought, maybe it does not like me using the same model, so I tried like this:

public ViewResult SomeAction(SomeModel model) 
{
    var newModel = new SomeModel { SomeString = "some value" };
    return View(newModel); 
}

And still the view renders with the original model. What’s odd is, when I put a breakpoint in the view and examine the model, it has the changed value. But the response stream has the old values.

Eventually I discovered the same work around that you did:

public ViewResult SomeAction(SomeModel model) 
{
    var newModel = new SomeModel { SomeString = "some value" };
    ModelState.Clear();
    return View(newModel); 
}

Works as expected.

I don’t think this is a “feature,” is it?

More Related Contents:

  1. How to get all Errors from ASP.Net MVC modelState?
  2. ASP.NET MVC – How to Preserve ModelState Errors Across RedirectToAction?
  3. How to replace the default ModelState error message in Asp.net MVC 2?
  4. MVC 4 Razor File Upload
  5. How to handle checkboxes in ASP.NET MVC forms?
  6. What is the ‘page lifecycle’ of an ASP.NET MVC page, compared to ASP.NET WebForms?
  7. ASP.NET MVC Ajax Error handling
  8. asp.net mvc put controllers into a separate project
  9. When to use TempData vs Session in ASP.Net MVC
  10. Handling session timeout in ajax calls
  11. ASP.NET MVC – Removing controller name from URL
  12. How to get Windows user name when identity impersonate=”true” in asp.net?
  13. Getting “The JSON request was too large to be deserialized”
  14. Razor View throwing “The name ‘model’ does not exist in the current context”
  15. Display DateTime value in dd/mm/yyyy format in Asp.NET MVC
  16. Return a JSON string explicitly from Asp.net WEBAPI?
  17. ASP.NET MVC – Custom validation message for value types
  18. ASP.NET MVC: Route with optional parameter, but if supplied, must match \d+
  19. Context.User.Identity.Name is null with SignalR 2.X.X. How to fix it?
  20. AllowAnonymous not working with Custom AuthorizationAttribute
  21. IIS hijacks CORS Preflight OPTIONS request
  22. ASP.NET MVC and mixed mode authentication
  23. How do I route a URL with a querystring in ASP.NET MVC?
  24. Recursion in an ASP.NET MVC view
  25. ASP.NET WebApi vs MVC? [closed]
  26. In what order are filters executed in asp.net mvc
  27. Hiddenfor not getting correct value from view model
  28. Get [DisplayName] attribute of a property in strongly-typed way
  29. Howto allow “Illegal characters in path”?
  30. Mapping Lists using Automapper

Leave a Comment