Question

Consider this HTML:

<div id=plan>
  <div id="plan-1" class='plan-hide'>One</div>
  <div id="plan-2" class='plan-hide'>Two</div>
  <div id="plan-3">Three</div>
  <div id="plan-4" class='plan-hide'>Four</div>
</div>

I want to hide all the plans (plan-1, plan-2, plan-3, plan-4) in the #plan

I have used regex [id^=plan-] but I believe its slow.

$("#slider").slider({
    range: "min",
    min: 0,
    max: 4
}, {
    slide: function( event, ui ) {
        $("[id^=plan-]").addClass('plan-hide');
        $("#plan-" + (ui.value+1)).removeClass('plan-hide');
    },
});

What is alternative way?

Answer 1

If you’re trying to add the class to all the elements in the container except the one that matches the ui value + 1, targeting all siblings is probably faster:

    slide: function( event, ui ) {
        $("#plan-" + (ui.value+1)).removeClass('plan-hide')
                                  .siblings().addClass('plan-hide');
    },

or even just:

    slide: function( event, ui ) {
        $('#plan').children('div').addClass('plan-hide');
        $("#plan-" + (ui.value+1)).removeClass('plan-hide');
    },

and probably fastest:

var elems = document.getElementById('plan').getElementsByTagName('div'),    
    len = elems.length;

$("#slider").slider({
    range: "min",
    min: 0,
    max: 4
}, {
    slide: function( event, ui ) {
        for (var i=0; i<len; i++) {
            elems[i].className = elems[i].id.indexOf(ui.value+1) != -1 ? '' : 'plan-hide';
        }
    },
});
​