So Code first add an easy way of doing this but if you don't want to design your form in code you can hook into the event model and add extra errors into the controller modelstate

So you'll need to look at http://our.umbraco.org/Documentation/Reference/Events/application-startup

And the event you need is  Umbraco.Forms.Mvc.Controllers.FormRenderController.FormValidate

The sender will be the controller so you can access the modelstate there and do stuff like

 ModelState.AddModelError(field.Id.ToString(),

                                         string.Format(errorMessage.ParsePlaceHolders(), field.Caption));

Will add a code sample tomorrow , need to run now

Ok so i have

        protected override void ApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
            Umbraco.Forms.Mvc.Controllers.FormRenderController.FormValidate += FormRenderControllerOnFormValidate;
        }

        private void FormRenderControllerOnFormValidate(object sender, FormViewEventArgs formViewEventArgs)
        {
            ModelState.AddModelError(field.Id.ToString(),string.Format(errorMessage.ParsePlaceHolders(), field.Caption));
        }

Do you know where ModelState is imported from?

I'll have a play around with it and see if i can get it working, failing that i'll wait for your code sample tomorrow.

Thanks Tim appreciate your help.

Yeah the sender is the controller, so cast to controller and then you should be able to access the modelstate

Ok cool, getting closer

protected override void ApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
           FormRenderController.FormValidate += FormRenderControllerOnFormValidate;
        }

        private void FormRenderControllerOnFormValidate(object sender , FormViewEventArgs formViewEventArgs)
        {
            //ModelState.AddModelError(field.Id.ToString(),string.Format(errorMessage.ParsePlaceHolders(), field.Caption));
            var s = sender as Controller;
            if (s != null)
            {
                s.ModelState.AddModelError(field.Id.ToString(), string.Format(errorMessage.ParsePlaceHolders(), field.Caption));
            }
            
        }

how to get the field.Id, is this the id of the Confirm Password field?

errorMessage.ParsePlaceHolders() doesnt resolve either

Hi Tim

Am i getting any closer on this? Don't suppose youve had time to knock an example together for me have you?

Cheers

Neil.

on it :)

Will have a working example in 30 mins 

Nice one, thanks Tim, apreciate it.

What is the best way to do the same type of validations (related form fields) but from Javascript (using Umbraco 4.11.9 and Contour 3.0.6)? Is there any example showing where to hook without to hack?

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