💾htmlElem.isHidden

💾 程式

// Geometry properties are calculated only for displayed elements.
// If an element (or any of its ancestors) has `display:none` or is 
// not in the document, then all geometry properties are 0.
Object.defineProperty(HTMLElement.prototype, 'isHidden', {
    get() { return !this.offsetWidth && !this.offsetHeight }
});

📗 參考

• JS.info ⟩ Element size and scrolling ⟩ offsetWidth/Height

📘 手冊

• HTMLElement ⟩ .offsetWidth