Rendering:
Demo code:
]<script>
function xstooltip_findPosX(obj)
{
var curleft = 0;
if (obj.offsetParent)
{
while (obj.offsetParent)
{
curleft += obj.offsetLeft
obj = obj.offsetParent;
}
}
else if (obj.x)
curleft += obj.x;
return curleft;
}
function xstooltip_findPosY(obj)
{
var curtop = 0;
if (obj.offsetParent)
{
while (obj.offsetParent)
{
curtop += obj.offsetTop
obj = obj.offsetParent;
}
}
else if (obj.y)
curtop += obj.y;
return curtop;
}
function xstooltip_show(tooltipId, parentId, posX, posY)
{
it = document.getElementById(tooltipId);
if ((it.style.top == '' || it.style.top == 0)
&& (it.style.left == '' || it.style.left == 0))
{
// need to fixate default size (MSIE problem)
it.style.width = it.offsetWidth + 'px';
it.style.height = it.offsetHeight + 'px';
img = document.getElementById(parentId);
// if tooltip is too wide, shift left to be within parent
if (posX + it.offsetWidth > img.offsetWidth) posX = img.offsetWidth - it.offsetWidth;
if (posX < 0 ) posX = 0;
x = xstooltip_findPosX(img) + posX;
y = xstooltip_findPosY(img) + posY;
it.style.top = y + 'px';
it.style.left = x + 'px';
}
it.style.visibility = 'visible';
}
function xstooltip_hide(id)
{
it = document.getElementById(id);
it.style.visibility = 'hidden';
}
</script>
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
