send http request in javascript code example

Example 1: javascript send post request

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"});

Example 2: javascript http request

// Use these functions:

function _GET_REQUEST(url, response) {
  var xhttp;
  if (window.XMLHttpRequest) {
    xhttp = new XMLHttpRequest();
  } else {
    xhttp = new ActiveXObject("Microsoft.XMLHTTP");
  }

  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      response(this.responseText);
    }
  };

  xhttp.open("GET", url, true);
  xhttp.send();
}

function _POST_REQUEST(url, params, response) {
  var xhttp;
  if (window.XMLHttpRequest) {
    xhttp = new XMLHttpRequest();
  } else {
    xhttp = new ActiveXObject("Microsoft.XMLHTTP");
  }

  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      response(this.responseText);
    }
  };

  xhttp.open("POST", url, true);
  xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
  xhttp.send(params);
}


// Use like:
_GET_REQUEST('http://url.com', (response) => {
	// Do something with variable response
  	console.log(response);
});
_POST_REQUEST('http://url.com', 'parameter=sometext', (response) => {
	// Do something with variable response
  	console.log(response);
});

Example 3: http request javascript

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);
}

Example 4: js make post request

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();