MyComponent.component.js

const MyComponent = (props) => {

  const formInput = React.createRef();
  
  const inputSelection = () => {
    const input = formInput.current;
    
    if (input.hasText()) {
      input.selectInputText();
    }
  };
  
  return (
    <div>
      <button type="button" onClick={inputSelection}>
        Select Input
      </button>
      
      <FormInput ref={formInput} />
    </div>
  );
  
};