使用jQuery切换元素宽度

Question

I have hamburger and menu on the left side, which has width: 0px;

How can I do after click on hamburger menu changes width to 250px , and second click change width to 0px ?

var hamburger = $('.hamburger-menu__list').css('width');

$('.hamburger-toggle').click(function(){
    $(this).toggleClass('open');
    if (hamburger == '0' ) {
        $('.hamburger-menu__list').css('width', 250);
    } 
    else {
        $('.hamburger-menu__list').css('width', 0);
    };
});

Answer 1

This will work. You have to check hamburger width everytime.

$('.hamburger-toggle').click(function(){
    var hamburger = $('.hamburger-menu__list').css('width');
    $(this).toggleClass('open');
    if (hamburger == '0' ) {
        $('.hamburger-menu__list').css('width', 250);
    } 
    else {
        $('.hamburger-menu__list').css('width', 0);
    };
});

Answer 2

You can still cache element but access width every time click is invoked.

Another suggestion is to use ternary-operator as this is ideal use case to use it.

 var hamburger = $('.hamburger-menu__list'); $('.hamburger-toggle').click(function() { $(this).toggleClass('open'); var hamburgerWidth = hamburger.css('width'); $('.hamburger-menu__list').css('width', hamburgerWidth == '0' ? 250 : 0); }); 

Answer 3

You need to check the width every time you click on the button, also you need to parseInt the width to get a right number, css('width') returns the value with prefix px eg 250px so parseInt will remove the prefix and returns pure number, Try this:

$('.hamburger-toggle').click(function(){
    var hamburgerWidth = parseInt($('.hamburger-menu__list').css('width'));

    $(this).toggleClass('open');

    if (hamburgerWidth === 0) {
        $('.hamburger-menu__list').css('width', 250);
    }  else {
        $('.hamburger-menu__list').css('width', 0);
    };
});

Answer 4

 var $hamburger = $('.hamburger-menu__list').css('width'), $hamburgerToggle = $('.hamburger-toggle'), isOpen = false; function toggleMenu() { isOpen = !isOpen; $hamburgerToggle.toggleClass('open', isOpen); $hamburger.width(isOpen ? 250 : 0); } $hamburgerToggle.click(toggleMenu); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> 

You are doing DOM manipulation. It is bad practice to relay on this, because it is asynchronous. A state variable ( isOpen ) helps to have only one source for the state (single source of truth).