DOM
document.querySelector('.sel') | Select element |
document.querySelectorAll('div') | Select all matching |
el.addEventListener('click', fn) | Add event listener |
el.removeEventListener('click', fn) | Remove listener |
el.classList.add/remove/toggle('cls') | Manage classes |
el.getAttribute('href') / setAttribute | Attributes |
el.textContent / innerHTML | Content (use textContent to avoid XSS) |
el.closest('.parent') | Find ancestor matching selector |
Fetch API
fetch(url).then(r=>r.json()) | GET request |
fetch(url,{method:'POST',body:JSON.stringify(d),headers:{'Content-Type':'application/json'} }) | POST JSON |
const resp = await fetch(url); if(!resp.ok) throw Error(resp.status); | Check status |
Storage
localStorage.setItem('k','v') | Persist to localStorage |
localStorage.getItem('k') | Get from localStorage |
sessionStorage.setItem('k','v') | Session-only storage |
document.cookie = 'k=v; path=/' | Set cookie |
Other APIs
navigator.clipboard.writeText(text) | Copy to clipboard |
navigator.geolocation.getCurrentPosition(cb) | Geolocation |
new IntersectionObserver(cb) | Intersection observer |
new MutationObserver(cb) | DOM mutation observer |
new ResizeObserver(cb) | Element resize observer |