Decimal values with thousand separator in Asp.Net MVC

Question

I have a custom model class which contains a decimal member and a view to accept entry for this class. Everything worked well till I added javascripts to format the number inside input control. The format code format the inputted number with thousand separator ',' when focus blur.

The problem is that the decimal value inside my modal class isn't bind/parsed well with thousand separator. ModelState.IsValid returns false when I tested it with "1,000.00" but it is valid for "100.00" without any changes.

Could you share with me if you have any solution for this?

Thanks in advance.

Sample Class

public class Employee
{
    public string Name { get; set; }
    public decimal Salary { get; set; }
}

Sample Controller

public class EmployeeController : Controller
{
    [AcceptVerbs(HttpVerbs.Get)]
    public ActionResult New()
    {
        return View();
    }

    [AcceptVerbs(HttpVerbs.Post)]
    public ActionResult New(Employee e)
    {
        if (ModelState.IsValid) // <-- It is retruning false for values with ','
        {
            //Subsequence codes if entry is valid.
            //
        }
        return View(e);
    }
}

Sample View

<% using (Html.BeginForm())
   { %>

    Name:   <%= Html.TextBox("Name")%><br />
    Salary: <%= Html.TextBox("Salary")%><br />

    <button type="submit">Save</button>

<% } %>

---

I tried a workaround with Custom ModelBinder as Alexander suggested. The probelm solved. But the solution doesn't go well with IDataErrorInfo implementation. The Salary value become null when 0 is entered because of the validation. Any suggestion, please? Do Asp.Net MVC team members come to stackoverflow? Can I get a little help from you?

Updated Code with Custom Model Binder as Alexander suggested

Model Binder

public class MyModelBinder : DefaultModelBinder {

    public override object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) {
        if (bindingContext == null) {
            throw new ArgumentNullException("bindingContext");
        }

        ValueProviderResult valueResult;
        bindingContext.ValueProvider.TryGetValue(bindingContext.ModelName, out valueResult);
        if (valueResult != null) {
            if (bindingContext.ModelType == typeof(decimal)) {
                decimal decimalAttempt;

                decimalAttempt = Convert.ToDecimal(valueResult.AttemptedValue);

                return decimalAttempt;
            }
        }
        return null;
    }
}

Employee Class

    public class Employee : IDataErrorInfo {

    public string Name { get; set; }
    public decimal Salary { get; set; }

    #region IDataErrorInfo Members

    public string this[string columnName] {
        get {
            switch (columnName)
            {
                case "Salary": if (Salary <= 0) return "Invalid salary amount."; break;
            }
            return string.Empty;
        }
    }

    public string Error{
        get {
            return string.Empty;
        }
    }

    #endregion
}

Answer 1

The reason behind it is, that in ConvertSimpleType in ValueProviderResult.cs a TypeConverter is used.

The TypeConverter for decimal does not support a thousand separator. Read here about it: http://social.msdn.microsoft.com/forums/en-US/clr/thread/1c444dac-5d08-487d-9369-666d1b21706e

I did not check yet, but at that post they even said the CultureInfo passed into TypeConverter is not used. It will always be Invariant.

           string decValue = "1,400.23";

        TypeConverter converter = TypeDescriptor.GetConverter(typeof(decimal));
        object convertedValue = converter.ConvertFrom(null /* context */, CultureInfo.InvariantCulture, decValue);

So I guess you have to use a workaround. Not nice...