Javascript check multiple inputs for blank, return one value

Question

Ok guys, before I continue, I know what I want to do could be done with numerous variables etc. but I've gotta imagine that what I'm doing can be done much more simply. So what I have is a form that has 4 fields and I want to check if anyone of the four are blank. Then each one that is blank, I want to add a class and use the jquery UI effect 'shake' to notify. Then I want to get a true or false response, true being that all aren't blank and false being that any one of the 4 is blank. so what I have is.. HTML...

<form name = "regin" id = "regin">
  <div id = "form_hold">
  <div><label>Username</label><input type="text" id = "Rusername" name = "Rusername" /><div class = 'verdiv' id = 'rvuname'></div></div>
  <div><label>Email</label><input type="text" id = "Remail" name = "Remail" /><div class = 'verdiv' id = 'rvemail'></div></div>
  <div><label>Password</label><input type="password" id = "Rpassword" name = "Rpassword" /><div class = 'verdiv' id = 'rvpass1'></div></div>
  <div><label>Confirm</label><input type="password" id = "Rpassword2" name = "Rpassword2" /><div class = 'verdiv' id = 'rvpass2'></div></div>
  </div>
  <button type="button" class = "thoughtbot" id = "registerButton">Register</button>
  </form>

and the javascript/jquery...

if($username == ''){
    $('#Rusername').parent().find('.verdiv').addClass('error');
    $('#Rusername').parent().effect("shake", { times:3 }, 50);
}
if($email == ''){
    $('#Remail').parent().find('.verdiv').addClass('error');
    $('#Remail').parent().effect("shake", { times:3 }, 50);
}   
if($password == ''){
    $('#Rpassword').parent().find('.verdiv').addClass('error');
    $('#Rpassword').parent().effect("shake", { times:3 }, 50);
}
if($checkval == ''){
    $('#Rpassword2').parent().find('.verdiv').addClass('error');
    $('#Rpassword2').parent().effect("shake", { times:3 }, 50); 
}

Now is there one top level function to 'test' each one of these statements to see if they're true? Thanks.

Answer 1

You could loop:

$('#Rusername, #Remail, #Rpassword, #Rpassword2').each(function() {
  if ($(this).val() == '') {
    $(this).parent().effect('shake', {times: 3}, 50).find('.verdiv').addClass('error');
  }
});

But ideally, I would add a class to their parent element and simplify the selector to just this:

$('.parent_class input');

EDIT: The code was not complete - I removed a left curly brace.

Answer 2

Put the same class on each of the input fields to be validated, for example validatefield.

Then assuming that $username and $email are the values of each input field, this should work:

var valid = true;
$(".validatefield").each(function() {
    if ($(this).val() == "") {
        $(this).parent().find('.verdiv').addClass('error');
        $(this).parent().effect("shake", { times:3 }, 50);
        valid = false;
    }
});