React Newline to break (nl2br)

Because you know that everything in React is functions, you can't really do this

this.state.text.replace(/(?:\r\n|\r|\n)/g, '<br />')

Since that would return a string with DOM nodes inside, that is not allowed either, because has to be only a string.

You then can try do something like this:

{this.props.text.split(“\n”).map(function(item) {
  return (
    {item}
    <br/>
  )
})}

That is not allowed either because again React is pure functions and two functions can be next to each other.

tldr. Solution

{this.props.text.split('\n').map(function(item, key) {
  return (
    <span key={key}>
      {item}
      <br/>
    </span>
  )
})}

Now we're wrapping each line-break in a span, and that works fine because span’s has display inline. Now we got a working nl2br line-break solution.

And ES6 version

{this.props.text.split('\n').map((item, key) => {
  return <span key={key}>{item}<br/></span>
})}

And with React Fragments

{this.props.text.split('\n').map((item, key) => {
  return <Fragment key={key}>{item}<br/></Fragment>
})}