React.isValidElement
Knowing what input type you've received is hugely important in JavaScript, which is a big reason for Flow and TypeScript's rise. One such case where it's useful to know what an object represents is if the input is a string or a React element.
To detect if an object is a React element, you can use React.isValidElement(obj):
// Add a wrapping DIV if the content isn't a React element
// PropTypes.oneOfType([PropTypes.string, PropTypes.element])
render() {
const { content } = this.props
React.isValidElement(content)) ?
content :
{content}
}
I really like that React.isValidElement allows us to create flexible elements that accept React elements or strings; hugely useful in generic components like modals, alerts, and everywhere else!
![9 Mind-Blowing Canvas Demos]()
The <canvas> element has been a revelation for the visual experts among our ranks. Canvas provides the means for incredible and efficient animations with the added bonus of no Flash; these developers can flash their awesome JavaScript skills instead. Here are nine unbelievable canvas demos that...
![CSS vs. JS Animation: Which is Faster?]()
How is it possible that JavaScript-based animation has secretly always been as fast — or faster — than CSS transitions? And, how is it possible that Adobe and Google consistently release media-rich mobile sites that rival the performance of native apps?
This article serves as a point-by-point...
![Create a Sexy Persistent Header with Opacity Using MooTools or jQuery]()
I've been working with the Magento eCommerce solution a lot lately and I've taken a liking to a technique they use with the top bar within their administrative control panel. When the user scrolls below a specified threshold, the top bar becomes attached to the...
![CSS pointer-events]()
The responsibilities taken on by CSS seems to be increasingly blurring with JavaScript. Consider the -webkit-touch-callout CSS property, which prevents iOS's link dialog menu when you tap and hold a clickable element. The pointer-events property is even more JavaScript-like, preventing:
click actions from doing...