Introduction

In HTML, if you want a textbox with some initial text you wrap text inside the textarea tag like this <textarea> Hello World </textarea>, this is fully editable, but if you try this in react you will get an error. Trying to use the defaultValue prop in react won't work either. if you add a value prop to the textarea the value of the text will be displayed but then it won't be editable, this is because the value prop is immutable.

Solution

Passing a value prop to textarea like this <textarea value={'Hello World'}> </textarea>, will display the text Hello World on the textbox, but it won't be editable to make it editable we need to pass the a state to the value prop and update that state with the onChange prop like the code below.

import { useState } from 'react';

function TextBox () {

    const [text, setText] = useState('Hello World');

   return (
           <textarea 
             value={text} 
             onChange={(e) => setText(e.target.value) }>
          </textarea>
         );

}

export default TextBox;

Inside the TextBox component, I initialize the text state with 'Hello World' and passed it to the textarea as a value prop, this will be the initial text displayed in the text area. onChange={(e) => setText(e.target.value) } this line of code updates the text state, with the new value.

You can learn more about handling form in react here