JAVASCRIPT

how to call url multiple times

for (i = 0; i < 2500; i++){
    var xhttp = new XMLHttpRequest();
    xhttp.onreadystatechange = function() {
        if (this.readyState == 4 && this.status == 200) {
            //do Something
        }
    };
    xhttp.open("GET", "http://localhost:63091/api/CustomerSite/GetSiteList?accessToken=123456789", true);
    xhttp.send();
}