旧demo

$(".buy_btn").click(function(){		$(".pop").fadeIn(300);		disable_scroll();			});	$("input[name='cancel']").click(function(){		$(".pop").fadeOut(300);		enable_scroll();	});var keys = [37, 38, 39, 40];function preventDefault(e) {  e = e || window.event;  if (e.preventDefault)      e.preventDefault();  e.returnValue = false;  }function keydown(e) {    for (var i = keys.length; i--;) {        if (e.keyCode === keys[i]) {            preventDefault(e);            return;        }    }}function wheel(e) {  preventDefault(e);}function disable_scroll() {  if (window.addEventListener) {      window.addEventListener('DOMMouseScroll', wheel, false);  }  window.onmousewheel = document.onmousewheel = wheel;  document.onkeydown = keydown;}function enable_scroll() {    if (window.removeEventListener) {        window.removeEventListener('DOMMouseScroll', wheel, false);    }    window.onmousewheel = document.onmousewheel = document.onkeydown = null;  }

新demo

$(".buy_btn").click(function(){		$(".pop").fadeIn(300);		disableScroll();			});	$("input[name='cancel']").click(function(){		$(".pop").fadeOut(300);		enableScroll()	});　　　　var keys = { 37: 1, 38: 1, 39: 1, 40: 1 };        function preventDefault(e) {            e = e || window.event;            if (e.preventDefault)                e.preventDefault();            e.returnValue = false;        }        function preventDefaultForScrollKeys(e) {            if (keys[e.keyCode]) {                preventDefault(e);                return false;            }        }        var oldonwheel, oldonmousewheel1, oldonmousewheel2, oldontouchmove, oldonkeydown        , isDisabled;        function disableScroll() {            if (window.addEventListener) // older FF                window.addEventListener('DOMMouseScroll', preventDefault, false);            oldonwheel = window.onwheel;            window.onwheel = preventDefault; // modern standard            oldonmousewheel1 = window.onmousewheel;            window.onmousewheel = preventDefault; // older browsers, IE            oldonmousewheel2 = document.onmousewheel;            document.onmousewheel = preventDefault; // older browsers, IE            oldontouchmove = window.ontouchmove;            window.ontouchmove = preventDefault; // mobile            oldonkeydown = document.onkeydown;            document.onkeydown = preventDefaultForScrollKeys;            isDisabled = true;        }        function enableScroll() {            if (!isDisabled) return;            if (window.removeEventListener)                window.removeEventListener('DOMMouseScroll', preventDefault, false);            window.onwheel = oldonwheel; // modern standard            window.onmousewheel = oldonmousewheel1; // older browsers, IE            document.onmousewheel = oldonmousewheel2; // older browsers, IE            window.ontouchmove = oldontouchmove; // mobile            document.onkeydown = oldonkeydown;            isDisabled = false;        }        window.scrollHanlder = {            disableScroll: disableScroll,            enableScroll: enableScroll        };