I just spent too much time banging me head against the wall trying yo get remote validation working. Each of the examples I found just did not seem to work, until I found this post from jquery4u.com. It used an interesting syntax that I had not seen anywhere. Until I found that post, all the examples used remote as an attribute under “rules”, but I could not seem to get it to work. The jquery4u syntax worked.
When I see multiple examples that I cannot get to work, I can never seem to let it go, so I started trying to get that syntax to work. I finally realized that, even though I had seen examples where data was passed, the way to get it to work was just to specify the URL and let jQuery validation do the rest. It creates a query param using the name you specify in the validator (so essentially your input name) as well as the value of the input. I finally got that working. This post from develoq.net helped set me straight.
My final struggle was to get unobtrusive validation working as well as an error message in my validation summary. I found how you can decorate an attribute on your model, but we use localization, and that just doesn;t work. We use FluentValidation, and that allows us to use our localization strings, so I wanted to see if FV could handle remote. It turns out it isn’t out of the box, but I found this post where a user created his own RemoteValidator.
It too me a while, but I knew it would and should all work!