How to post a json array in react native

var item ={} // declaring object array
var array =[] // declaring array
item["id"] = '824233';              //adding object to the object array
item["project_id"] = ' 1457';
item["issue_id"] = '123420';
item["activity_id"] = '71';
item["comments"] = 'Testing';

array.push(item) // pushing the object in the declared array 
var strArray =JSON.stringify(array);// stringify the array 

//regular api call fetch('https:www.yourapi.com', { method: 'POST', headers: { 'Accept': 'application/json', 'Content-Type': 'application/json', }, body: JSON.stringify(strArray) })

Just use JSON.stringify(yourArray) to convert the array JSON object to a string, then post it.

var myArray = [
    {
        "id": 824233,
        "project_id": 1457,
        "issue_id": 123420,
        "activity_id": 71,
        "comments": "Testing",
    },
    {
        "id": 824234,
        "project_id": 1457,
        "issue_id": 123420,
        "activity_id": 188,
        "comments": "test",
    },
    {
        "id": 824235,
        "project_id": 1457,
        "issue_id": 123420,
        "activity_id": 188,
        "comments": "Test",
    }
];

fetch('https://mywebsite.com/endpoint/', {
  method: 'POST',
  headers: {
    'Accept': 'application/json',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify(myArray)
})

Source: https://facebook.github.io/react-native/docs/network.html#making-requests

Ahmed is right you have to stringify your JSON when using fetch. JQuery and other libraries do this for you automatically.

I created a small helper function to use with fetch that stringifies your data for you and has some other built in magic.

export default function headersFactory(jwtToken) {
  return function headers(method, data) {
    const header = {
      mode: 'cors',
      method,
      headers: {
        Accept: 'application/json',
        'Content-Type': 'application/json',
      },
    };
    if (jwtToken) header.headers.Authorization = `Bearer ${jwtToken.hash}`;
    if (data) header.body = JSON.stringify(data);
    return header;
  };
}

Now you can call it like this:

import headersFactory from './headersFactory';

fetch('https://mywebsite.com/endpoint/', headersFactory(token)('post', myArray))
  .then(res => res.json())
  .then(data => console.log(data));

The token argument is for auth and is optional you can also call it like:

// this
const headers1 = headersFactory()('post', myArray);

// or this
const headers2 = headersFactory()('get');

// or this
const headers3 = headersFactory({ hash: 'asdfo3qi38094' })('delete');

you can do for loops and post for each element of that array via fetch