fetch get and post of javascript

index.php

<?php

var_dump($_POST);die;

script.js

function postData(url, data) {
            // Default options are marked with *
            data = Object.keys(data).map(key => encodeURIComponent(key) + '=' + encodeURIComponent(data[key])).join('&')

            return fetch(url, {
               // body:data,
              body: (data), // must match 'Content-Type' header
              cache: 'no-cache', // *default, no-cache, reload, force-cache, only-if-cached
              credentials: 'same-origin', // include, same-origin, *omit
              headers: {
                'Accept': 'application/json, application/xml, text/plain, text/html, *.*',
                'Content-Type': 'application/x-www-form-urlencoded; charset=utf-8'
            
              },
              method: 'POST', // *GET, POST, PUT, DELETE, etc.
              mode: 'cors', // no-cors, cors, *same-origin
              redirect: 'follow', // manual, *follow, error
              referrer: 'no-referrer', // *client, no-referrer
            })
            .then(response => response.json()) // parses response to JSON
          }

//this.newUser
//object
//newUser.name='csf',
//newUser.age=2
            
            
          this.postData('index.php', 
           // {
               // answer: 42,
             //   data:JSON.stringify(this.newUser),
            //},
            this.newUser
        )

//method get jsut basic

fetch('index_data.php')
      .then(res => res.json())
      .then(res => {
          this.cats = res;
      })



//more
//https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API/Using_Fetch
//https://github.com/matthew-andrews/isomorphic-fetch/issues/30
////https://stackoverflow.com/a/45345813/3633498
//https://github.github.io/fetch/