var xmlhttp = new XMLHttpRequest();
xmlhttp.open("GET", $urlEnvio, false);
xmlhttp.setRequestHeader("accept" ,"application/json");
xmlhttp.setRequestHeader("content-type" ,"application/json");
xmlhttp.send($urlEnvio);

var resultado = xmlhttp.response;
var elementos =JSON.parse(resultado);

axios.get(urlEnvio, usuario, clave)
.then(response => {
  // JSON responses are automatically parsed.
  this.posts = response.data
  //var elementos = JSON.stringify(posts);
  alert(posts[0]);

})

var elementos = [];
axios.get(urlEnvio, usuario, clave)
.then(response => {
  // JSON responses are automatically parsed.
  elementos = response.data;
});

var elementos = [];
axios.get(urlEnvio, , {
 params: {
   user: usuario,
   pass: clave
 }
})
.then(response => {
  // JSON responses are automatically parsed.
  elementos = response.data;
});

$response = [];
$response['logged'] = false;
if($_GET['user']=="oxxido" && $_GET['pass']=="superseguro") {
  $response['logged'] = true;
}
echo json_encode($response);

// GET request
axios.get('https://api.github.com/users/oxxido')
  .then(function(response){
    console.log(response.data); // ex.: { user: 'Your User'}
    console.log(response.status); // ex.: 200
  });

// guardando POST request
axios.post('/save', { firstName: 'Oxxido', lastName: 'Test' })
  .then(function(response){
    console.log('Guardado exitoso')
  });