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!
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Back in late 2012 it was not easy to find open source projects using requestAnimationFrame() - this is the hook that allows Javascript code to synchronize with a web browser's native paint loop. Animations using this method can run at 60 fps and deliver fantastic...
![Detect DOM Node Insertions with JavaScript and CSS Animations]()
I work with an awesome cast of developers at Mozilla, and one of them in Daniel Buchner. Daniel's shared with me an awesome strategy for detecting when nodes have been injected into a parent node without using the deprecated DOM Events API.
![Detect DOM Node Insertions with JavaScript and CSS Animations]()
I work with an awesome cast of developers at Mozilla, and one of them in Daniel Buchner. Daniel's shared with me an awesome strategy for detecting when nodes have been injected into a parent node without using the deprecated DOM Events API.
![CSS :target]()
One interesting CSS pseudo selector is :target. The target pseudo selector provides styling capabilities for an element whose ID matches the window location's hash. Let's have a quick look at how the CSS target pseudo selector works!
The HTML
Assume there are any number of HTML elements with...