Question

it seems simple, but I couldn’t figure how to intercept numbers on javascript from Document DOM

    $(document).keypress(function (e) {
        if (e.keyCode == xx) {
            alert();
        }
    });

Answer 1

Numbers are 48 through 57, so…

$(document).keypress(function (e) {
    var key = e.keyCode || e.charCode;
    if (key >= 48 && key <= 57) {
        alert('You pressed ' + (key - 48));
    }
});

See demo