jQuery Form Validation before Ajax submit

You could use the submitHandler option. Basically put the $.ajax call inside this handler, i.e. invert it with the validation setup logic.

$('#form').validate({

    ... your validation rules come here,

    submitHandler: function(form) {
        $.ajax({
            url: form.action,
            type: form.method,
            data: $(form).serialize(),
            success: function(response) {
                $('#answers').html(response);
            }            
        });
    }
});

The jQuery.validate plugin will invoke the submit handler if the validation has passed.

first you don't need to add the classRules explicitly since required is automatically detected by the jquery.validate plugin. so you can use this code :

1. on form submit , you prevent the default behavior
2. if the form is Invalid stop the execution.
3. else if valid send the ajax request.

$('#form').submit(function (e) {
  e.preventDefault();
  var $form = $(this);

  // check if the input is valid using a 'valid' property
  if (!$form.valid) return false;

  $.ajax({
    type: 'POST',
    url: 'add.php',
    data: $('#form').serialize(),
    success: function (response) {
      $('#answers').html(response);
    },
  });
});

You can try doing:

if($("#form").validate()) {
 return true;
} else {
 return false;
}