how to send post request in fetch code example

Example 1: react post request

componentDidMount() {
    // Simple POST request with a JSON body using fetch
    const requestOptions = {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ title: 'React POST Request Example' })
    };
    fetch('https://jsonplaceholder.typicode.com/posts', requestOptions)
        .then(response => response.json())
        .then(data => this.setState({ postId: data.id }));
}

Example 2: post fetch call

async function postData(url = '', data = {}) {
  // Default options are marked with *
  const response = await fetch(url, {
    method: 'POST', // *GET, POST, PUT, DELETE, etc.
    mode: 'cors', // no-cors, *cors, same-origin
    cache: 'no-cache', // *default, no-cache, reload, force-cache, only-if-cached
    credentials: 'same-origin', // include, *same-origin, omit
    headers: {
      'Content-Type': 'application/json'
      // 'Content-Type': 'application/x-www-form-urlencoded',
    },
    redirect: 'follow', // manual, *follow, error
    referrerPolicy: 'no-referrer', // no-referrer, *no-referrer-when-downgrade, origin, origin-when-cross-origin, same-origin, strict-origin, strict-origin-when-cross-origin, unsafe-url
    body: JSON.stringify(data) // body data type must match "Content-Type" header
  });
  return response.json(); // parses JSON response into native JavaScript objects
}

postData('', )
  .then(data => {
    console.log(data); // JSON data parsed by `data.json()` call
  });