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onChangeTo handle events on the select element in React :

1. Set the attribute on the select element onChange.
2. Save the value of the selected option in a state variable.
3. Each time the user changes the selected option, update the state variable.

import {useState} from 'react';

const App = () => {
  const options = [
    {value: '', text: '--Choose an option--'},
    {value: 'apple', text: 'Apple 🍏'},
    {value: 'banana', text: 'Banana 🍌'},
    {value: 'kiwi', text: 'Kiwi 🥝'},
  ];

  const [selected, setSelected] = useState(options[0].value);

  const handleChange = event => {
    console.log(event.target.value);
    setSelected(event.target.value);
  };

  return (
    <div>
      <select value={selected} onChange={handleChange}>
        {options.map(option => (
          <option key={option.value} value={option.value}>
            {option.text}
          </option>
        ))}
      </select>
    </div>
  );
};

export default App;

This example defines all options in an array to make our JSX code more concise, but we could write each option element manually.

If we prefer to enter the options manually, check out the last code snippet in the article.

We use useStatethe hook to store the value of the selected option.

The argument we pass to the hook is the initial state. In the example, we set the value of the initial selection to an empty string, which is the value of the first option element.

If we want a different option to be initially selected, pass its value to useStatethe hook.

We set the attribute on the selectonChange element , so every time its value changes, handleChangethe function will be called.

const handleChange = event => {
  console.log(event.target.value);
  setSelected(event.target.value);
};

The target property of the event object refers to the select element, so we can access the selected value as event.target.value.

In our handleChangefunction, we simply update the state with the value of the selected option.

If we need to get the text associated with the selected option element, access the label attribute of the selected option.

const handleChange = event => {
  console.log('Label 👉️', event.target.selectedOptions[0].label);

  console.log(event.target.value);
  setSelected(event.target.value);
};

Here is an example of how to map()manually enter the options for a select element without using .

import {useState} from 'react';

const App = () => {
  // 👇️ initial value of empty string (first option)
  const [selected, setSelected] = useState('');

  const handleChange = event => {
    console.log('Label 👉️', event.target.selectedOptions[0].label);
    console.log(event.target.value);
    setSelected(event.target.value);
  };

  return (
    <div>
      <select value={selected} onChange={handleChange}>
        <option value="">--Choose and option--</option>
        <option value="apple">Apple 🍏</option>
        <option value="banana">Banana 🍌</option>
        <option value="kiwi">Kiwi 🥝</option>
      </select>
    </div>
  );
};

export default App;

We set an initial value of an empty string for selectthe element, which will render the first option.

We can change the default selected option by providing a different initial value, such as apple .

Make sure the initial value is one of the possible values ​​for the attribute optionon the element value.