<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>function (e,t){return new x.fn.init(e,t,r)}var ContactForm = jQuery('#contact');   //указываем id формы 
 ContactForm.find("#data_contact").val().length>0               
&& emailReg.test((ContactForm.find("#data_email").val()))
&& ContactForm.find("#data_comments").val().length>0