function ajax(settings){
    let request = new XMLHttpRequest();
    let data = new FormData();

    request.open(settings.method||"get", settings.url, settings.async || false);
    if(settings.method == "post"){
        request.setRequestHeader("ContentType", "application/x-www-form-urlencoded; charset=utf-8")
    }
    request.onreadystatechange = function(){
        if(request.readyState == 4)
            settings.ready?.apply(this);
        else
            settings.upload?.apply(this);
    }

    for(let i in settings.data)
        data.append(i, settings.data[i]);

    request.send(data);
}