Question

I have a form and unfortunately built it without the help of external libraries (which I am now cursing myself for not including). So my form validation isn’t just form.validate() or something similar, it’s going to have to be an archaic javascript method (time constraints means I cannot implement external libraries because it’d involve rebuilding the form).

All I want is to check all the fields have been filled in – no email validation or post-code validation etc.

I tried a simple version:

if((document.getElementById("fieldA").value != "") || (document.getElementById("fieldB").value != "")){
   alert("form okay");
}else{
   alert("form not okay");
}

but this doesn’t work. The alternative to this would be to nest 45 if statements detecting each field individually but this is tedious and unfeasible.

Answer 1

you can loop trough elements in the form with

document.forms[0].elements

like

 var d = document.forms[0].elements
 var l = d.length;
 for(var i = 0; i < l; i ++) {
     var element = d[i];
     var type = element.type;
     var value = element.value;
     var class = element.className;
 }

dropdown:

document.forms[0].select.value

radiobuttons:

for (i=0;i<document.forms[0].radios.length;i++) {
    if (document.forms[0].radios[i].checked) {
        var value = document.forms[0].radios[i].value;
    }
}

thanks to external libraries we don’t need that to do ourselves these days😉