Validate field, select or checkbox without form tag

Good day,

I found a lot of topics about that, but, without a proper answer.

Many of topics ended with question why you just can't add form?

I'm working on a project that based on ASP.NET and I have one form tag, one form tag that contains all the html code inside it.

I can't use any ASP.NET controls and must done validation by front-end (jQuery).

Everything is fine when there is only one form and one submit button, then I can use simple query validation plugin, but it gets complicated when I have more than one form and of course more than one submit button.

Any suggestion, ideas or real example how to do that?

Maybe I can somehow put every field and submit button inside a div and validate them by submit within that div?

Thank you!