How to check without inside a #id has a . class?

Question

Has a top #header that adds the class .hide-bar when scroll but when returning to the top, this class.

How to check with jQuery if you are class is present in this id or not? I need this check to disappear/return with certain blocks.

Answer 1

You can use the method .hasClass() jQuery:

if($('#header').hasClass('hide-bar')){
    // fazer algo caso tenha a classe
}

I usually avoid jQuery whenever possible in simple features like this. To do this with native Javascript can do so:

var elemento = document.getElementById('header');
if(elemento.className.indexOf('hide-bar') != -1){
    // fazer algo caso tenha a classe
}

Or using Javascript in modern browsers (IE9+):

var elemento = document.getElementById('header');
if(elemento.classList.contains('hide-bar')1){
    // fazer algo caso tenha a classe
}