jQuery-有条件地循环访问元素到addClass（）

Question

I have a few input fields that I'm trying to add a class to their parent container if they are not empty.

Here's the CoffeeScript:

$(".inputA, .inputB").parent().addClass(->
        if !$(this).is(":empty")
            "input-set"
    )

This is successfully appending "input-set" to the parent class, but in all cases, not just empty input fields.

:(

Answer 1

:empty will select elements that don't have children. Therefore, using it to conditionally select the parents of certain elements doesn't make any sense.

ref: https://developer.mozilla.org/en-US/docs/Web/CSS/:empty

If you're looking to add the class to the parents of inputs that haven't been populated then you could use something like:

$(".inputA, .inputB").each(function(){
    if (this.value !== "") {
        $(this).parent().addClass('input-set');
    }
});

Answer 2

Use jQuery.filter()

$(".inputA, .inputB").filter(function(){
    return this.value !='';
}).parent().addClass("input-set");

Less function calls than using $.each

Answer 3

First, input elements are by definition empty..

Read the :empty documentation at http://api.jquery.com/empty-selector/

Second you are testing the parent elements and not the input ones.. ( and since they are parents, meaning they are not empty they all fit the bill.. )