How to determine validity of form field from view file?

I am using the MVC client side validation. I am generating the form fields within the view like this:

         <% using (Html.BeginForm(new { useCIM = false }))
           {%>           
        <%: Html.ValidationMessage("auth")%>
        <%: Html.TextBoxFor(model => model.Country)%>
        <%: Html.TextBoxFor(model => model.Zip)%>

I can access the specific Validation Messages within the view like this:

            <%: Html.ValidationMessageFor(model => model.Country)%>
            <%: Html.ValidationMessageFor(model => model.Zip)%>

How can I simply determine the validity of a specific f开发者_开发知识库ield?

UPDATE***

When I try to...

<% if (ModelState["Country"].Errors > 0)

I get an error that "System.Web.Mvc.ModelState' is a 'type' but is used like a 'variable'"

Use

ModelState["Fieldname"].Errors.Count > 0;

In .aspx page use

<% if(ViewData.ModelState["Fieldname"].Errors.Count > 0)%>

On client side check for field with CSS class

"input-validation-error"

In addition to what Emmanuel N said, if you simply want to know in the view if the field is valid, you can use this:

ViewData.ModelState.IsValidField("Fieldname")