How to interrupt form submission in bitrix?

Question

JavaScript

Good afternoon!
I can’t figure out how to stop submitting the form to Bitrix, this method doesn’t work:

var formID = "form_" + "<?=CUtil::JSEscape($arResult['FORM_ID'])?>";
var form = BX(formID);
var sourceEl = BX.findChild(form, { "tag":"select", "attr": { "name": "SOURCE_ID" } }, true, false);

BX.bind(form, 'submit', function(){
    var id = sourceEl.value;
    if(id == 20){
       alert(id);
       return false;
    }
});

alert fires but the submit is still in progress, how can I prevent the form from submitting?

Answer 1

have you tried that?
BX.bind(form, 'submit', function(event){
var id = sourceEl.value;
if(id == 20){
event.preventDefault() ;
event.stopPropagation();
alert(id);
}
}) ;

Answer 2

If it’s not so easy to get into the form code, then it’s easier to set disabled for an option that does not need to be selected, you can also hang custom validation on this select and if the form is sent via submit, then the sending will not be completed

Answer 3

and what's stopping you from sending via jikveri or vanillage