fetch method in javascript code example

Example 1: js fetch 'post' json

//Obj of data to send in future like a dummyDb
const data = { username: 'example' };

//POST request with body equal on data in JSON format
fetch('https://example.com/profile', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify(data),
})
.then((response) => response.json())
//Then with the data from the response in JSON...
.then((data) => {
  console.log('Success:', data);
})
//Then with the error genereted...
.catch((error) => {
  console.error('Error:', error);
});

//																		Yeah

Example 2: Add no cores to fetch

// There were no quick access to mode and credentials to other fetch answers.
// Data you'll be sending
const data = { funny: "Absolutely not", educational: "yas" }

fetch('https://example.com/api/', {
  method: 'POST', // The method
  mode: 'no-cors', // It can be no-cors, cors, same-origin
  credentials: 'same-origin', // It can be include, same-origin, omit
  headers: {
    'Content-Type': 'application/json', // Your headers
  },
  body: JSON.stringify(data),
}).then(returnedData => {
  // Do whatever with returnedData
}).catch(err => {
  // In case it errors.
})

Example 3: javascript fetch api

fetch('http://example.com/movies.json')
  .then((response) => {
    return response.json();
  })
  .then((data) => {
    console.log(data);
  });

Example 4: fetch api javascript

fetch('http://example.com/songs')
	.then(response => response.json())
	.then(data => console.log(data))
	.catch(err => console.error(err));

Example 5: fetch

// This will fetch api.example.com/comments with a header and a body
fetch(`https://api.example.com/comments`, {
  method: 'POST', //This could be any http method
  headers: {
    'Authorization': 'Basic SGVsbG8gdGhlcmUgOikgSGF2ZSBhIGdvb2QgZGF5IQ==',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
	UID: 58,
    Comment: "Fetch is really easy!",
  }),
})
.then((response) => response.json())
.then((newComment) => {
  // Do something magical with your newly posted comment :)
});

Example 6: fetch method in javascript

// Example POST method implementation:
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('https://example.com/answer', { answer: 42 })
  .then(data => {
    console.log(data); // JSON data parsed by `data.json()` call
  });