[Solved] How to return error information to grid in ajax editing mode

[Jao]

Hi!
Is there a way to tell the user who currently inserting or editing grid row the that some special kind of data error occured. For instance attempt to create duplicate record or attempt to violate any other database logic. GridModel allows me to specify updated data only, not error code or message. And second. I would like to use some complex validation logic with localized validation error messages when processing CRUD ajax requests. How can I achieve that?
Example code:

var entity = new Entity();
if (TryUpdateModel(entity))
{
	Repository.Entities.InsertOnSubmit(entity);
	Repository.SubmitChanges();
} // need else branch to display model state errors to user
return View(new GridModel(Repository.Entities));

Thank you.

[Jao]

// Controller
[AcceptVerbs(HttpVerbs.Post)]
[GridAction]
public ActionResult _InsertEntityt()
{
	var entity = new Entity();
	if (TryUpdateModel(entity))
	{
		Repository.Entities.InsertOnSubmit(entity);
		Repository.SubmitChanges();
	}
	else
	{
		Response.StatusCode = 500;
                return Content(String.Join(
                    " ",
                    (from state in ModelState select state)
                        .SelectMany(s => s.Value.Errors)
                        .Select(e => e.ErrorMessage)
                        .ToArray()));
	}
	return View(new GridModel(Repository.Entities));
}
// View
<%=
	Html.Telerik().(...).ClientEvents(events => events.OnError("onError"))
%>
<script type="text/javascript">
    function onError(e) {
        if (e.textStatus == 'error'){
            if (e.XMLHttpRequest.status == "500") {
                alert("The server was unable to process your request.\n" + e.XMLHttpRequest.responseText);
                e.preventDefault();
            }
        }
    }
</script>

[Jao]

I'm sure all the logic above should be incapsulated into HandleGridError filter attribute.

[Saul]

How would you do this if IIS is set to use the default error pages? When I deploy this solution I do not get the error message rather the text from the default error page.

Thanks

[Xavi]

You are the man.
Thanks for sharing

[Mano]

But how do you handle for Successful Adding/Editing of the record. Can somebody please point out a direction to look into?