You Don't Need jQuery

Frontend environments evolve rapidly nowadays, modern browsers have already implemented a great deal of DOM/BOM APIs which are good enough. We don't have to learn jQuery from scratch for DOM manipulation or events. In the meantime, thanks to the prevailment of frontend libraries such as React, Angular and Vue, manipulating DOM directly becomes anti-pattern, jQuery has never been less important. This project summarizes most of the jQuery method alternatives in native implementation, with IE 10+ support.

Table of Contents

1. Query Selector
2. CSS & Style
3. DOM Manipulation
4. Ajax
5. Events
6. Utilities
7. Translation
8. Browser Support

Query Selector

In place of common selectors like class, id or attribute we can use document.querySelector or document.querySelectorAll for substitution. The differences lie in:

• document.querySelector returns the first matched element
• document.querySelectorAll returns all matched elements as NodeList. It can be converted to Array using [].slice.call(document.querySelectorAll(selector) || []);
• If no elements matched, jQuery would return [] whereas the DOM API will return null. Pay attention to Null Pointer Exception. You can also use || to set default value if not found, like document.querySelectorAll(selector) || []

Notice: document.querySelector and document.querySelectorAll are quite SLOW, try to use getElementById, document.getElementsByClassName or document.getElementsByTagName if you want to get a performance bonus.

• 1.0 Query by selector

  // jQuery
  $('selector');
  
  // Native
  document.querySelectorAll('selector');

• 1.1 Query by class

  // jQuery
  $('.class');
  
  // Native
  document.querySelectorAll('.class');
  
  // or
  document.getElementsByClassName('class');

• 1.2 Query by id

  // jQuery
  $('#id');
  
  // Native
  document.querySelector('#id');
  
  // or
  document.getElementById('id');

• 1.3 Query by attribute

  // jQuery
  $('a[target=_blank]');
  
  // Native
  document.querySelectorAll('a[target=_blank]');

• 1.4 Find sth.

  • Find nodes

    // jQuery
    $el.find('li');
    
    // Native
    el.querySelectorAll('li');

  • Find body

    // jQuery
    $('body');
    
    // Native
    document.body;

  • Find Attribute

    // jQuery
    $el.attr('foo');
    
    // Native
    e.getAttribute('foo');

  • Find data attribute

    // jQuery
    $el.data('foo');
    
    // Native
    // using getAttribute
    el.getAttribute('data-foo');
    // you can also use `dataset` if only need to support IE 11+
    el.dataset['foo'];

• 1.5 Sibling/Previous/Next Elements

  • Sibling elements

    // jQuery
    $el.siblings();
    
    // Native
    [].filter.call(el.parentNode.children, function(child) {
      return child !== el;
    });

  • Previous elements

    // jQuery
    $el.prev();
    
    // Native
    el.previousElementSibling;

  • Next elements

    // next
    $el.next();
    el.nextElementSibling;

• 1.6 Closest

  Return the first matched element by provided selector, traversing from current element to document.

  // jQuery
  $el.closest(queryString);
  
  // Native
  function closest(el, selector) {
    const matchesSelector = el.matches || el.webkitMatchesSelector || el.mozMatchesSelector || el.msMatchesSelector;
  
    while (el) {
      if (matchesSelector.call(el, selector)) {
        return el;
      } else {
        el = el.parentElement;
      }
    }
    return null;
  }

• 1.7 Parents Until

  Get the ancestors of each element in the current set of matched elements, up to but not including the element matched by the selector, DOM node, or jQuery object.

  // jQuery
  $el.parentsUntil(selector, filter);
  
  // Native
  function parentsUntil(el, selector, filter) {
    const result = [];
    const matchesSelector = el.matches || el.webkitMatchesSelector || el.mozMatchesSelector || el.msMatchesSelector;
  
    // match start from parent
    el = el.parentElement;
    while (el && !matchesSelector.call(el, selector)) {
      if (!filter) {
        result.push(el);
      } else {
        if (matchesSelector.call(el, filter)) {
          result.push(el);
        }
      }
      el = el.parentElement;
    }
    return result;
  }

• 1.8 Form

  • Input/Textarea

    // jQuery
    $('#my-input').val();
    
    // Native
    document.querySelector('#my-input').value;

  • Get index of e.currentTarget between .radio

    // jQuery
    $(e.currentTarget).index('.radio');
    
    // Native
    [].indexOf.call(document.querySelectAll('.radio'), e.currentTarget);

• 1.9 Iframe Contents

  $('iframe').contents() returns contentDocument for this specific iframe

  • Iframe contents

    // jQuery
    $iframe.contents();
    
    // Native
    iframe.contentDocument;

  • Iframe Query

    // jQuery
    $iframe.contents().find('.css');
    
    // Native
    iframe.contentDocument.querySelectorAll('.css');

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CSS & Style

• 2.1 CSS

  • Get style

    // jQuery
    $el.css("color");
    
    // Native
    // NOTE: Known bug, will return 'auto' if style value is 'auto'
    const win = el.ownerDocument.defaultView;
    // null means not return presudo styles
    win.getComputedStyle(el, null).color;

  • Set style

    // jQuery
    $el.css({ color: "#ff0011" });
    
    // Native
    el.style.color = '#ff0011';

  • Get/Set Styles

    Note that if you want to set multiple styles once, you could refer to setStyles method in oui-dom-utils package.

  • Add class

    // jQuery
    $el.addClass(className);
    
    // Native
    el.classList.add(className);

  • Remove class

    // jQuery
    $el.removeClass(className);
    
    // Native
    el.classList.remove(className);

  • has class

    // jQuery
    $el.hasClass(className);
    
    // Native
    el.classList.contains(className);

  • Toggle class

    // jQuery
    $el.toggleClass(className);
    
    // Native
    el.classList.toggle(className);

• 2.2 Width & Height

  Width and Height are theoretically identical, take Height as example:

  • Window height

    // window height
    $(window).height();
    // without scrollbar, behaves like jQuery
    window.document.documentElement.clientHeight;
    // with scrollbar
    window.innerHeight;

  • Document height

    // jQuery
    $(document).height();
    
    // Native
    document.documentElement.scrollHeight;

  • Element height

    // jQuery
    $el.height();
    
    // Native
    function getHeight(el) {
      const styles = this.getComputedStyles(el);
      const height = el.offsetHeight;
      const borderTopWidth = parseFloat(styles.borderTopWidth);
      const borderBottomWidth = parseFloat(styles.borderBottomWidth);
      const paddingTop = parseFloat(styles.paddingTop);
      const paddingBottom = parseFloat(styles.paddingBottom);
      return height - borderBottomWidth - borderTopWidth - paddingTop - paddingBottom;
    }
    // accurate to integer（when `border-box`, it's `height`; when `content-box`, it's `height + padding + border`）
    el.clientHeight;
    // accurate to decimal（when `border-box`, it's `height`; when `content-box`, it's `height + padding + border`）
    el.getBoundingClientRect().height;

• 2.3 Position & Offset

  • Position

    // jQuery
    $el.position();
    
    // Native
    { left: el.offsetLeft, top: el.offsetTop }

  • Offset

    // jQuery
    $el.offset();
    
    // Native
    function getOffset (el) {
      const box = el.getBoundingClientRect();
    
      return {
        top: box.top + window.pageYOffset - document.documentElement.clientTop,
        left: box.left + window.pageXOffset - document.documentElement.clientLeft
      }
    }

• 2.4 Scroll Top

  // jQuery
  $(window).scrollTop();
  
  // Native
  (document.documentElement && document.documentElement.scrollTop) || document.body.scrollTop;

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DOM Manipulation

• 3.1 Remove

  // jQuery
  $el.remove();
  
  // Native
  el.parentNode.removeChild(el);

• 3.2 Text

  • Get text

    // jQuery
    $el.text();
    
    // Native
    el.textContent;

  • Set text

    // jQuery
    $el.text(string);
    
    // Native
    el.textContent = string;

• 3.3 HTML

  • Get HTML

    // jQuery
    $el.html();
    
    // Native
    el.innerHTML;

  • Set HTML

    // jQuery
    $el.html(htmlString);
    
    // Native
    el.innerHTML = htmlString;

• 3.4 Append

  append child element after the last child of parent element

  // jQuery
  $el.append("<div id='container'>hello</div>");
  
  // Native
  let newEl = document.createElement('div');
  newEl.setAttribute('id', 'container');
  newEl.innerHTML = 'hello';
  el.appendChild(newEl);

• 3.5 Prepend

  // jQuery
  $el.prepend("<div id='container'>hello</div>");
  
  // Native
  let newEl = document.createElement('div');
  newEl.setAttribute('id', 'container');
  newEl.innerHTML = 'hello';
  el.insertBefore(newEl, el.firstChild);

• 3.6 insertBefore

  Insert a new node before the selected elements

  // jQuery
  $newEl.insertBefore(queryString);
  
  // Native
  newEl.insertBefore(document.querySelector(queryString));

• 3.7 insertAfter

  Insert a new node after the selected elements

  // jQuery
  $newEl.insertAfter(queryString);
  
  // Native
  function insertAfter(newEl, queryString) {
    const parent = document.querySelector(queryString).parentNode;
  
    if (parent.lastChild === newEl) {
      parent.appendChild(newEl);
    } else {
      parent.insertBefore(newEl, parent.nextSibling);
    }
  },

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Ajax

Replace with fetch and fetch-jsonp

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Events

For a complete replacement with namespace and delegation, refer to https://github.com/oneuijs/oui-dom-events

• 5.1 Bind an event with on

  // jQuery
  $el.on(eventName, eventHandler);
  
  // Native
  el.addEventListener(eventName, eventHandler);

• 5.2 Unbind an event with off

  // jQuery
  $el.off(eventName, eventHandler);
  
  // Native
  el.removeEventListener(eventName, eventHandler);

• 5.3 Trigger

  // jQuery
  $(el).trigger('custom-event', {key1: 'data'});
  
  // Native
  if (window.CustomEvent) {
    const event = new CustomEvent('custom-event', {detail: {key1: 'data'}});
  } else {
    const event = document.createEvent('CustomEvent');
    event.initCustomEvent('custom-event', true, true, {key1: 'data'});
  }
  
  el.dispatchEvent(event);

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Utilities

• 6.1 isArray

  // jQuery
  $.isArray(range);
  
  // Native
  Array.isArray(range);

• 6.2 Trim

  // jQuery
  $.trim(string);
  
  // Native
  string.trim();

• 6.3 Object Assign

  Extend, use object.assign polyfill https://github.com/ljharb/object.assign

  // jQuery
  $.extend({}, defaultOpts, opts);
  
  // Native
  Object.assign({}, defaultOpts, opts);

• 6.4 Contains

  // jQuery
  $.contains(el, child);
  
  // Native
  el !== child && el.contains(child);

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Translation

• 한국어
• 简体中文
• Bahasa Melayu
• Bahasa Indonesia
• Português(PT-BR)
• Tiếng Việt Nam

Browser Support

Latest ✔	Latest ✔	10+ ✔	Latest ✔	6.1+ ✔

License

MIT