do a request get with ajax code example

Example: ajax get js

let xhr = new XMLHttpRequest();

xhr.open("GET", "une/url");

xhr.responseType = "json";

xhr.send();

xhr.onload = function(){
    if (xhr.status != 200){ 
        alert("Erreur " + xhr.status + " : " + xhr.statusText);
    }else{ 
        alert(xhr.response.length + " octets  téléchargés\n" + JSON.stringify(xhr.response));
    }
};

xhr.onerror = function(){
    alert("La requête a échoué");
};

xhr.onprogress = function(event){
    if (event.lengthComputable){
        alert(event.loaded + " octets reçus sur un total de " + event.total);
    }
};