Migrate from React string refs

Identify any string refs in the component, e.g., ref="someRef".

Step 1: Declare ref fields

Declare ref fields in the class constructor (or as a class property).

Before

// Old
ref="someRef"

After

// New
constructor(props) {
  super(props)
  this.someRef = React.createRef()
}

Step 2: Update elements

Update all elements that used string refs to use object refs.

Before

// Old
const value = this.refs.someRef.value

After

// New
const value = this.someRef.current.value