Trouble with Model.IsValid on a property thats not required - asp.net-mvc-3

Question

I am having trouble with Model.IsValid on a property that's not required.
Here's the code.
BeginForm in the Edit.cshtml file
#using (Html.BeginForm("Edit", "Member", FormMethod.Post, new { enctype = "multipart/formdata" }))
{
#Html.Partial("_MemberForm", Model.Member)
}
MemberEditViewModel: (used for the Edit.cshtml file)
public class MemberEditViewModel
{
public MemberFormModel Member { get; set; }
}
MemberFormModel:
public class MemberFormModel : ICreateMemberCommand, IValidatableObject
{
public int Id { get; set; }
[Required]
public string FirstName { get; set; }
[Required]
public string LastName { get; set; }
[Required]
public string SocialSecurityNumber { get; set; }
[Required]
public int PinCode { get; set; }
[Required]
public char Gender { get; set; }
public string Email { get; set; }
[Required]
public string Address { get; set; }
[Required]
public string ZipCode { get; set; }
[Required]
public string ZipAddress { get; set; }
public string Phone { get; set; }
public string Phone2 { get; set; }
[Required]
public string City { get; set; }
[Required]
public int CountryId { get; set; }
//not required (but still displaying error it's required)
public Membership Membership { get; set; }
// not required (displaying error it's required)
public PunchCard PunchCard { get; set; }
public bool IsActive { get; set; }
block of _MemberForm.cshtml (partial)
<fieldset>
<dl>
<dt>#Html.LabelFor(m => m.Id)</dt>
<dd>#Html.TextBoxFor(m => m.Id, new { disabled = "disabled", #readonly = "readonly" })</dd>
<dt>#Html.LabelFor(m => m.PinCode)</dt>
<dd>#Html.EditorFor(m => m.PinCode)</dd>
<!-- problem with membership, maybe with the .FromData/ToDate ? -->
<dt>#Html.LabelFor(m => m.Membership)</dt>
<dd>#Html.EditorFor(m => m.Membership.FromDate, new { #name = "Membership" }) -
#Html.EditorFor(m => m.Membership.ToDate, new { #name="Membership"})</dd>
<!-- problem with punch card, maybe with the .Times ? -->
<dt>#Html.LabelFor(m => m.PunchCard)</dt>
<dd>#Html.EditorFor(m => m.PunchCard.Times, new { #name = "PunchCard" })</dd>
</dl>
</fieldset>
The MemberController Edit Action
// POST: /Members/10002/Edit
[HttpPost]
public ActionResult Edit(FormCollection formValues, MemberFormModel memberForm)
{
var errors = ModelState.Values.SelectMany(v => v.Errors);
if(IsSaveOperation(formValues)){
if(TryUpdateMember(memberForm)){
return RedirectToAction("Details", "Member", new {id = memberForm.Id});
}
}
var mm = new MemberEditViewModel{ Member = memberForm };
return View(mm);
}
Membership.cs
public class Membership
{
public Membership(){ /* empty constructor */}
public Membership(int id, int memberId, DateTime fromDate, DateTime toDate)
{
Id = id;
MemberId = memberId;
FromDate = fromDate;
ToDate = toDate;
}
public int Id { get; set; }
public int MemberId { get; set; }
[DataType(DataType.Date)]
public DateTime FromDate { get; set; }
[DataType(DataType.Date)]
public DateTime ToDate { get; set; }
}
PunchCard.cs
public class PunchCard
{
public PunchCard() { /* empty constructor */ }
public PunchCard(int memberId, int times, DateTime createdDate, DateTime modifiedDate)
{
this.MemberId = memberId;
this.Times = times;
this.CreatedDate = createdDate;
this.ModifiedDate = modifiedDate;
}
public int Id { get; set; }
public int MemberId { get; set; }
public int Times { get; set; }
public DateTime CreatedDate { get; set; }
public DateTime ModifiedDate { get; set; }
}
You see I dont have any [Required] attribute, neither in the MemberFormModel. So how come those two are Required ? Its a mystery.

Answer 1

You should not be using both the disabled and readonly attribute on your textbox:
#Html.TextBoxFor(m => m.Id, new { disabled = "disabled", #readonly = "readonly" })
I guess the disabled attribute takes precedence and the value of the Id is never sent to the server when you submit the form. That's why you get a modelstate error. Because your id property is required. Now you will be probably tell me that it is not decorated with the [Required] attribute but this doesn't matter. Since you have declared it as a non-nullable integer it is implicitly required and the framework automatically makes it required. If you don't want this to happen you should declare it as a nullable integer.
So back to your view, if you want to only display id, without allowing the user to modify it, use readonly:
#Html.TextBoxFor(m => m.Id, new { #readonly = "readonly" })
Obviously don't think that if you made a textbox readonly, the user cannot modify it. The normal user will not. But a hacker could always put whatever value he wants in this textbox and forge a request. So absolutely do not rely on this as some sort of security or something.