$(document).hover(function(e) {
    alert(e.type === 'mouseenter' ? 'enter' : 'leave');
});

小提琴

You can test with jQuery if any child div has a certain class. Then by applying that class when you mouse over and out out a certain div, you can test whether your mouse is over it, even when you mouse over a different element on the page Much less code this way. I used this because I had spaces between divs in a pop-up, and I only wanted to close the pop up when I moved off of the pop up, not when I was moving my mouse over the spaces in the pop up. So I called a mouseover function on the content div (which the pop up was over), but it would only trigger the close function when I moused-over the content div, AND was outside the pop up!

$(".pop-up").mouseover(function(e)
    {
    $(this).addClass("over");
    });

$(".pop-up").mouseout(function(e)
    {
    $(this).removeClass("over");
    });


$("#mainContent").mouseover(function(e){
            if (!$(".expanded").hasClass("over")) {
            Drupal.dhtmlMenu.toggleMenu($(".expanded"));
        }
    });

你可以使用jQuery的悬停事件来手动跟踪:

$(...).hover(
    function() { $.data(this, 'hover', true); },
    function() { $.data(this, 'hover', false); }
).data('hover', false);

if ($(something).data('hover'))
    //Hovered!

在jQuery中，你可以使用.is(':hover')

function IsMouseOver(oi)
{
   return $(oi).is(':hover');
}

现在是提供OP中请求的函数的最简洁的方式。

注意:以上操作在IE8及以下版本中无效

作为在IE8中工作的不那么简洁的替代方案(如果我可以信任IE9的IE8模式)，并且这样做没有触发$(…).hover(…)到处都是，也不需要知道元素的选择器(在这种情况下Ivo的答案更容易):

function IsMouseOver(oi)
{
    return oi.length && 
           oi.parent()
             .find(':hover')
             .filter(function(s){return oi[0]==this})
             .length > 0;
}

一个干净优雅的悬停检查:

if ($('#element:hover').length != 0) {
    // do something ;)
}

扩展什么'Happytime harry'说，一定要使用.data() jquery函数来存储超时id。这样，当'mouseenter'在同一个元素上被触发时，你可以很容易地检索超时id，允许你消除触发，让你的工具提示消失。