Question

I’m using an entity model with metadata annotations. My controller method looks like this…

        if (!ModelState.IsValid)
        {
            return View(model);
        }
        else
        {
            UpdateModel(model);
            repo.Save();
            return RedirectToAction("Index");
        }

If I enable client side validation in the view I’ll get the error per the Attributes from the metadata class. If I take clientside validation out, error gets thrown from saving to the DB rather than return the view with an Error Summary.

This is the top portion of my view….

<% using (Html.BeginForm())
   {%>
<%: Html.ValidationSummary(true) %>

I’ve tried running without debugging (ctrl + f5) in debug and release mode as well as setting breakpoints and Debugging (f5) but it just seems weird to get Client side validation without server side validation. What am I missing here?

Answer 1

UpdateModel populates the model from form collection, routing parameters, etc. and does validation on the server side. You need to check ModelState.IsValid after updating. The usual pattern is…

if (!TryUpdateModel(model))
{
  // Validation Failed...
  return View(model);
}

// Validation Passed...

Note that TryUpdateModel catches exceptions and returns false if they’re raised. If they aren’t, then it simple returns ModelState.IsValid.