$("#btn").bind("click",function(e){
if(e.stopPropagation){//需要阻止冒泡
e.stopPropagation();
}else{
e.cancelBubble = true;
}
})

$(document).bind("click",function(e){
if(點擊事件不在model上){
隱藏模態框;
}
})

$("#modal").bind("click", function(event) {
if (event && event.stopPropagation) {
event.stopPropagation();
} else {
event.cancelBubble = true;
}

});

$(document).one("click", function(e){
var $target = $(e.currentTarget);
if ($target.attr("id") != "modal") {
$("#modal").css("display", "none");
}
});