Values retained during post back in MVC

Question

Suppose i have a model with a validation

public class LoginModel
{
    [Required(ErrorMessage="ID not entered")]
    [StringLength(5,ErrorMessage = "Length should be 5")]
    public string Id { get; set; }




}

In the view page i have a text box. When the validation fails. The controller returns to the view page with error message.

public ActionResult Login()
    {
        return View();
    }

    [HttpPost]
    public ActionResult Login(LoginModel lg)
    {
        if(ModelState.IsValid)
        {
            return RedirectToAction("Index", "Home");

        }
        return View();

    }

But the text box contains the previous values. How does it retains the value? And is there any way to avoid it?

Thanks

nWorx · Answer 1 · 2011-07-22T11:42:42.183

1

to delete the data just try the link which rattlemouse has posted -

ModelState.Clear()

or you do it manually with

 [HttpPost]
    public ActionResult Login(LoginModel lg)
    {
        if(ModelState.IsValid)
        {
            return RedirectToAction("Index", "Home");

        }
       else{
             lg.Id = string.Empty;
             return View(lg);
        }

    }

edited Jul 22 '11 at 11:42

answered Jul 20 '11 at 12:27

nWorx

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even without passing the model, its retaining the value. But is there any way to avoid it? – Thomas Mathew Jul 21 '11 at 07:00

score 0 · Answer 2 · answered Apr 13 '17 at 21:48

Clear ModelState and return view without model.

  ModelState.Clear();
  return View();

ModelState

Controller.ModelState Property

ModelState is a property of a Controller, and can be accessed from those classes that inherit from System.Web.Mvc.Controller. The ModelState represents a collection of name and value pairs that were submitted to the server during a POST. It also contains a collection of error messages for each value submitted.

Values retained during post back in MVC

2 Answers2