(My apologies if this seems verbose - trying to provide all relevant code)
I've just upgraded to VS2010, and am now having trouble trying to get a new CustomModelBinder working.
In MVC1 I would have written something like
public class AwardModelBinder: DefaultModelBinder
{
:
public override object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
// do the base binding to bind all simple types
Award award = base.BindModel(controllerContext, bindingContext) as Award;
// Get complex values from ValueProvider dictionary
award.EffectiveFrom = Convert.ToDateTime(bindingContext.ValueProvider["Model.EffectiveFrom"].AttemptedValue.ToString());
string sEffectiveTo = bindingContext.ValueProvider["Model.EffectiveTo"].AttemptedValue.ToString();
if (sEffectiveTo.Length > 0)
award.EffectiveTo = Convert.ToDateTime(bindingContext.ValueProvider["Model.EffectiveTo"].AttemptedValue.ToString());
// etc
return award;
}
}
Of course I'd register the custom binder in Global.asax.cs:
protected void Application_Start()
{
RegisterRoutes(RouteTable.Routes);
// register custom model binders
ModelBinders.Binders.Add(typeof(Voucher), new VoucherModelBinder(DaoFactory.UserInstance("EH1303")));
ModelBinders.Binders.Add(typeof(AwardCriterion), new AwardCriterionModelBinder(DaoFactory.UserInstance("EH1303"), new VOPSDaoFactory()));
ModelBinders.Binders.Add(typeof(SelectedVoucher), new SelectedVoucherModelBinder(DaoFactory.UserInstance("IT0706B")));
ModelBinders.Binders.Add(typeof(Award), new AwardModelBinder(DaoFactory.UserInstance("IT0706B")));
}
Now, in MVC2, I'm finding that my call to base.BindModel returns an object where everything is null, and I simply don't want to have to iterate all the form fields surfaced by the new ValueProvider.GetValue() function.
Google finds no matches for this error, so I assume I'm doing something wrong.
Here's my actual code:
My domain object (infer what you like about the encapsulated child objects - I know I'll need custom binders for those too, but the three "simple" fields (ie. base types) Id, TradingName and BusinessIncorporated are also coming back null):
public class Customer
{
/// <summary>
/// Initializes a new instance of the Customer class.
/// </summary>
public Customer()
{
Applicant = new Person();
Contact = new Person();
BusinessContact = new ContactDetails();
BankAccount = new BankAccount();
}
/// <summary>
/// Gets or sets the unique customer identifier.
/// </summary>
public int Id { get; set; }
/// <summary>
/// Gets or sets the applicant details.
/// </summary>
public Person Applicant { get; set; }
/// <summary>
/// Gets or sets the customer's secondary contact.
/// </summary>
public Person Contact { get; set; }
/// <summary>
/// Gets or sets the trading name of the business.
/// </summary>
[Required(ErrorMessage = "Please enter your Business or Trading Name")]
[StringLength(50, ErrorMessage = "A maximum of 50 characters is permitted")]
public string TradingName { get; set; }
/// <summary>
/// Gets or sets the date the customer's business began trading.
/// </summary>
[Required(ErrorMessage = "You must supply the date your business started trading")]
[DateRange("01/01/1900", "01/01/2020", ErrorMessage = "This date must be between {0} and {1}")]
public DateTime BusinessIncorporated { get; set; }
/// <summary>
/// Gets or sets the contact details for the customer's business.
/// </summary>
public ContactDetails BusinessContact { get; set; }
/// <summary>
/// Gets or sets the customer's bank account details.
/// </summary>
public BankAccount BankAccount { get; set; }
}
My controller method:
/// <summary>
/// Saves a Customer object from the submitted application form.
/// </summary>
/// <param name="customer">A populate instance of the Customer class.</param>
/// <returns>A partial view indicating success or failure.</returns>
/// <httpmethod>POST</httpmethod>
/// <url>/Customer/RegisterCustomerAccount</url>
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult RegisterCustomerAccount(Customer customer)
{
if (ModelState.IsValid)
{
// save the Customer
// return indication of success, or otherwise
return PartialView();
}
else
{
ViewData.Model = customer;
// load necessary reference data into ViewData
ViewData["PersonTitles"] = new SelectList(ReferenceDataCache.Get("PersonTitle"), "Id", "Name");
return PartialView("CustomerAccountRegistration", customer);
}
}
My custom binder:
public class CustomerModelBinder : DefaultModelBinder
{
public override object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
ValueProviderResult vpResult = bindingContext
.ValueProvider.GetValue(bindingContext.ModelName);
// vpResult is null
// MVC2 - ValueProvider is now an IValueProvider, not dictionary based anymore
if (bindingContext.ValueProvider.GetValue("Model.Applicant.Title") != null)
{
// works
}
Customer customer = base.BindModel(controllerContext, bindingContext) as Customer;
// customer instanitated with null (etc) throughout
return customer;
}
}
My binder registration:
/// <summary>
/// Application_Start is called once when the web application is first accessed.
/// </summary>
protected void Application_Start()
{
RegisterRoutes(RouteTable.Routes);
// register custom model binders
ModelBinders.Binders.Add(typeof(Customer), new CustomerModelBinder());
ReferenceDataCache.Populate();
}
... and a snippet from my view (could this be a prefix problem?)
<div class="inputContainer">
<label class="above" for="Model_Applicant_Title" accesskey="t"><span class="accesskey">T</span>itle<span class="mandatoryfield">*</span></label>
<%= Html.DropDownList("Model.Applicant.Title", ViewData["PersonTitles"] as SelectList, "Select ...",
new { @class = "validate[required]" })%>
<% Html.ValidationMessageFor(model => model.Applicant.Title); %>
</div>
<div class="inputContainer">
<label class="above" for="Model_Applicant_Forename" accesskey="f"><span class="accesskey">F</span>orename / First name<span class="mandatoryfield">*</span></label>
<%= Html.TextBox("Model.Applicant.Forename", Html.Encode(Model.Applicant.Forename),
new { @class = "validate[required,custom[onlyLetter],length[2,20]]",
title="Enter your forename",
maxlength = 20, size = 20,
autocomplete = "off",
onkeypress = "return maskInput(event,re_mask_alpha);"
})%>
</div>
<div class="inputContainer">
<label class="above" for="Model_Applicant_MiddleInitials" accesskey="i">Middle <span class="accesskey">I</span>nitial(s)</label>
<%= Html.TextBox("Model.Applicant.MiddleInitials", Html.Encode(Model.Applicant.MiddleInitials),
new { @class = "validate[optional,custom[onlyLetter],length[0,8]]",
title = "Please enter your middle initial(s)",
maxlength = 8,
size = 8,
autocomplete = "off",
onkeypress = "return maskInput(event,re_mask_alpha);"
})%>
</div>
