Question

I’m currently using ASP.NET MVC3 RC and I’m using the unobtrusive JQuery validations as described by Brad Wilson on his blog. It works great but when I send my form (in Ajax) to the server, I do some server side validations and return the same row (that is included in a partial view) if my model state isn’t valid. 2 problems with that :

1st : When I do a return PartialView in my action, all the unobtrusive attributes aren’t rendered. I found a “non elegant” way to do it but when I do it, client validations are broken. After I return from my action, even if I call jQuery.validator.unobtrusive.parse() on my updated row, $("form").valid() always return true even if it’s not the case.

2nd : I want my rendered view to be render as a string on the server so I can send it back in a JsonResult (ex:myJSonResult.html=RenderPartialToString("partialName",model)).

Has a reference, there’s my view (editInvitation) :

<td>
    <%= Html.HiddenFor(x=>x.ID,new{id="ID"}) %>
    <%= Html.HiddenFor(x=>x.GroupID,new{id="GroupID"})  %>
    <%: Html.TextBoxFor(x => x.Name, new { id = "Name" })%><%:Html.ValidationMessageFor(x=>x.Name) %>
</td>
<td>
    <%: Html.TextBoxFor(x => x.Email, new { id = "Email" })%>  <%:Html.ValidationMessageFor(x=>x.Email) %>
</td>
<td>
    <%: Model.Status.ToFriendlyName()%>
</td>
<td>
  <%= InvitationsViewModel.RenderActions(Model, Html, InvitationsViewModel.CreateRowID(Model.ID))%>
</td>

And my controller action :

if (TryUpdateModel(invitation))
{
    validModel = true;
    //Other stuff
}
if (Request.IsAjaxRequest())
{
     //TODO : I return a partial view but I would prefer to return a JSonResult with the rendered view as a string in an Property of my JSon result
     return PartialView(validModel ? "DisplayInvitation" : "EditInvitation", invitation);
}

Thanks

Answer 1

I finally make it worked. This is how :

HtmlHelper helper = GetHelper();
MvcHtmlString partialView = helper.Partial("myView" , model);
var result = new { success = ModelState.IsValid, html = partialView.ToString() };
return Json(result);

There’s the helper functions:

protected HtmlHelper GetHelper()
{
    return GetHelper(string.Empty);
}
protected HtmlHelper GetHelper(string formID)
{
    HtmlHelper helper = new HtmlHelper(getViewContext(formID), new ViewPage { ViewData = this.ViewData });
    helper.EnableClientValidation(isClientValidationEnabled());
    helper.EnableUnobtrusiveJavaScript(isUnobtrusiveJavascriptEnabled());
    return helper;
}
private ViewContext getViewContext(string formID)
{
    var vc = new ViewContext(this.ControllerContext, new WebFormView(this.ControllerContext, "~/Views/Home/Index.aspx"), this.ViewData, new TempDataDictionary(), new System.IO.StringWriter());
    vc.UnobtrusiveJavaScriptEnabled = isUnobtrusiveJavascriptEnabled();
    vc.ClientValidationEnabled = isClientValidationEnabled();
    vc.FormContext = new FormContext { FormId = formID };
    return vc;
}

I’m not sure it’s the best way to do it but it worked for me. Let’s hope the ASP.NET MVC team would provide an easier way to render a view as a string.

Thanks