SOURCE

$(document).bind("contextmenu", function () { return false; });//禁止右键
document.oncontextmenu = function () { return false; };
document.onkeydown = function () {
    if (window.event && window.event.keyCode == 123) {
        event.keyCode = 0;
        event.returnValue = false;
        return false;
    }
};//禁止F12

阻止用户按F12