"Type arguments cannot be inferred" error when using Html.TextboxFor with a ViewModel in an ASP.NET MVC 2 View

Question

I'm writing an ASP.NET MVC 2 site where I have defined a custom ViewModel that I'm trying to use in a View. Unfortunately, I'm running into an error when using the ViewModel through a strongly-typed lambda expression.

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My Code

Here's my ViewModel:

    [CompareProperties(ComparisonProperty1="EmailAddress", ComparisonProperty2="ConfirmEmailAddress",LessThanAllowed=false,EqualToAllowed=true,GreaterThanAllowed=false,AllowNullValues=true,ErrorMessage="You must enter the same email address in both fields.")]
    public class OpenIdRegistrationViewModel
    {
        [Required(ErrorMessage="You must specify an email address.")]
        [DisplayName("Email address")]
        [IsValidEmailAddress(ErrorMessage="This is not a valid email address.")]
        public string EmailAddress
        {
            get;
            set;
        }
        [Required(ErrorMessage = "You must enter you email address a second time.")]
        [DisplayName("Confirm email address")]
        [IsValidEmailAddress(ErrorMessage = "This is not a valid email address.")]
        public string ConfirmEmailAddress
        {
            get;
            set;
        }
        [DisplayName("Nickname")]
        [Required(ErrorMessage="You must choose a Nickname.")]
        public string Username
        {
            get;
            set;
        }
        [Required(ErrorMessage="An OpenID claim must be included.")]
        public Identifier OpenIdClaim
        {
            get;
            set;
        }
    }

I'm trying to use the ViewModel in a View like this:

<%@ Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<OpenidRegistrationViewModel>" %>


<asp:Content ID="registerContent" ContentPlaceHolderID="MainContent" runat="server">
    <%= Html.ValidationSummary("Account creation was unsuccessful. Please correct the errors and try again.") %>

    <% using (Html.BeginForm()) { %>
        <div>
            <fieldset>
                <legend>Account Information</legend>
                <p>
                    <%= Html.LabelFor(m=>m.Username) %>
                    <%= Html.TextBoxFor(m=>m.Username)%>
                    <%= Html.ValidationMessageFor(m=>m.Username) %>
                </p>
                <!-- etc. -->
                <p>
                    <input type="submit" value="Register" />
                </p>
            </fieldset>
        </div>
    <% } %>
</asp:Content>

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The Error

However, I'm getting a compiler error on each of the lines where I use a lambda expression (such as Html.LabelFor, Html.TextBoxFor, etc.). Here's the error:

The type arguments for method 'System.Web.Mvc.Html.InputExtensions.TextBoxFor(System.Web.Mvc.HtmlHelper, System.Linq.Expressions.Expression>)' cannot be inferred from the usage. Try specifying the type arguments explicitly.

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I don't understand what's wrong. Do you see any errors in my code?

Thanks in advance.

Answer 1

Not sure if this is something to do with it:

public class OpenIdRegistrationViewModel

And:

Inherits="System.Web.Mvc.ViewPage<OpenidRegistrationViewModel>"

You've got a case typo OpenidRegistrationViewModel != OpenIdRegistrationViewModel.