$(window).keypress(function(event) {
    if (!(event.which == 115 && event.ctrlKey) && !(event.which == 19)) return true;
    alert("Ctrl-S pressed");
    event.preventDefault();
    return false;
});

$(window).bind('keydown', function(event) {
    if (event.ctrlKey || event.metaKey) {
        switch (String.fromCharCode(event.which).toLowerCase()) {
        case 's':
            event.preventDefault();
            alert('ctrl-s');
            break;
        case 'f':
            event.preventDefault();
            alert('ctrl-f');
            break;
        case 'g':
            event.preventDefault();
            alert('ctrl-g');
            break;
        }
    }
});

shortcut.add("Ctrl+S",function() {
    alert("Hi there!");
});

$(document).keydown(function(event) {

    //19 for Mac Command+S
    if (!( String.fromCharCode(event.which).toLowerCase() == 's' && event.ctrlKey) && !(event.which == 19)) return true;

    alert("Ctrl-s pressed");

    event.preventDefault();
    return false;
});

$(document).keydown(function(e) {
    if ((e.which == '115' || e.which == '83' ) && (e.ctrlKey || e.metaKey))
    {
        e.preventDefault();
        alert("Ctrl-s pressed");
        return false;
    }
    return true;
});

// simply disables save event for chrome
$(window).keypress(function (event) {
    if (!(event.which == 115 && (navigator.platform.match("Mac") ? event.metaKey : event.ctrlKey)) && !(event.which == 19)) return true;
    event.preventDefault();
    return false;
});

// used to process the cmd+s and ctrl+s events
$(document).keydown(function (event) {
     if (event.which == 83 && (navigator.platform.match("Mac") ? event.metaKey : event.ctrlKey)) {
        event.preventDefault();
        save(event);
        return false;
     }
});

var ctrl_down = false;
var ctrl_key = 17;
var s_key = 83;

$(document).keydown(function(e) {
    if (e.keyCode == ctrl_key) ctrl_down = true;
}).keyup(function(e) {
    if (e.keyCode == ctrl_key) ctrl_down = false;
});

$(document).keydown(function(e) {
    if (ctrl_down && (e.keyCode == s_key)) {
        alert('Ctrl-s pressed');
        // Your code
        return false;
    }
});