jquery – 确定html元素的可见性/实际z-index

function elementWithinElement(elemPossiblyCovered,elemPossiblyCovering)
{
    var top = elemPossiblyCovered.offsetTop;
    var left = elemPossiblyCovered.offsetLeft;
    var width = elemPossiblyCovered.offsetWidth;
    var height = elemPossiblyCovered.offsetHeight;

    while (elemPossiblyCovered.offsetParent)
    {
        elemPossiblyCovered = elemPossiblyCovered.offsetParent;
        top += elemPossiblyCovered.offsetTop;
        left += elemPossiblyCovered.offsetLeft;
    }

    return (
    top >= elemPossiblyCovering.offsetTop &&
    left >= elemPossiblyCovering.offsetLeft &&
    (top + height) <= (elemPossiblyCovering.offsetTop + elemPossiblyCovering.offsetHeight) &&
    (left + width) <= (elemPossiblyCovering.offsetLeft + elemPossiblyCovering.offsetWidth)
  );
}

所以它是这样的：

if(elementWithinElement(myTextBox,theDatepickerDiv))
{ 
    // It's hidden
}else
{
    //It's visible
}

编辑：部分代码未更新.现在应该修好.

再次编辑：修复代码并测试它.有用！