React.isValidElement

By  on  

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!

Recent Features

  • By
    CSS Gradients

    With CSS border-radius, I showed you how CSS can bridge the gap between design and development by adding rounded corners to elements.  CSS gradients are another step in that direction.  Now that CSS gradients are supported in Internet Explorer 8+, Firefox, Safari, and Chrome...

  • By
    5 Awesome New Mozilla Technologies You’ve Never Heard Of

    My trip to Mozilla Summit 2013 was incredible.  I've spent so much time focusing on my project that I had lost sight of all of the great work Mozillians were putting out.  MozSummit provided the perfect reminder of how brilliant my colleagues are and how much...

Incredible Demos

  • By
    TextboxList for MooTools and jQuery by Guillermo Rauch

    I'll be honest with you: I still haven't figured out if I like my MooTools teammate Guillermo Rauch. He's got a lot stacked up against him. He's from Argentina so I get IM'ed about 10 times a day about how great Lionel...

  • By
    CSS Custom Cursors

    Remember the Web 1.0 days where you had to customize your site in every way possible?  You abused the scrollbars in Internet Explorer, of course, but the most popular external service I can remember was CometCursor.  CometCursor let you create and use loads of custom cursors for...

Discussion

    Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!