javascript send post

let data = {element: "barium"};

fetch("/post/data/here", {
  method: "POST", 
  body: JSON.stringify(data)
}).then(res => {
  console.log("Request complete! response:", res);
});


// If you are as lazy as me (or just prefer a shortcut/helper):

window.post = function(url, data) {
  return fetch(url, {method: "POST", body: JSON.stringify(data)});
}

// ...

post("post/data/here", {element: "osmium"});
function httpGetAsync(url, callback) {
  var xmlHttp = new XMLHttpRequest();
  xmlHttp.onreadystatechange = function() { 
    if (xmlHttp.readyState == 4 && xmlHttp.status == 200)
      callback(xmlHttp.responseText);
  }
  xmlHttp.open("GET", url, true); // true for asynchronous 
  xmlHttp.send(null);
}const postData = async ( url = '', data = {})=>{
    console.log(data);
      const response = await fetch(url, {
      method: 'POST', 
      credentials: 'same-origin',
      headers: {
          'Content-Type': 'application/json',
      },
     // Body data type must match "Content-Type" header        
      body: JSON.stringify(data), 
    });

      try {
        const newData = await response.json();
        console.log(newData);
        return newData;
      }catch(error) {
      console.log("error", error);
      }
  }
var xhr = new XMLHttpRequest();
xhr.open("POST", yourUrl, true);
xhr.setRequestHeader('Content-Type', 'application/json');
xhr.send(JSON.stringify({
    value: value
}));var xhr = new XMLHttpRequest();
// we defined the xhr

xhr.onreadystatechange = function () {
    if (this.readyState != 4) return;

    if (this.status == 200) {
        var data = JSON.parse(this.responseText);

        // we get the returned data
    }

    // end of state change: it can be after some time (async)
};

xhr.open('GET', yourUrl, true);
xhr.send();