Add class when (...) with jQuery

I've this simple code:

HTML:

<input type="text" name="name" class="required" />

<select id="options" name="options" size="1">
  <option value="0"> YES </option>
  <option value="1"> NO </option>
</select>


<input type="text" name="email" />
<input type="text" name="city" />

Question:

I want to add class = "required" to email and city fields when options is e开发者_运维问答qual to 1

Something like:

$('#options').change(function() {
    $('input[name="email"], input[name="city"]')
       .toggleClass('required', this.value === '1');
});

Reference: change, toggleClass

I've added Id's to your input elements to make the selector quicker:

 <input type="text" name="email" id="email" />
 <input type="text" name="city" id="city" />

jQuery:

$("#options").change(function() {
    if ($(this).val() == "1") {
        $("#email, #city").addClass("required");
    }
    else {
        $("#email, #city").removeClass("required");
    }
});

if( $('#options').val() == "1"){
   $('#email, #city').addClass('required');
}

assign ids to the inputs and do following logic , ids are always better as it takes less time to execute in case of complex DOMs.

$('#options').change(function(){
if($(this).val() == 1) {
 $('#inputemail').addClass('required');
 $('#city').addClass('required');
}else {
$('#inputemail').removeClass('required');
 $('#city').removeClass('required');
}
});