Javascript:如何检测浏览器窗口是否滚动到底部?

I need to detect if a user is scrolled to the bottom of a page. If they are at the bottom of the page, when I add new content to the bottom, I will automatically scroll them to the new bottom. If they are not at the bottom, they are reading previous content higher on the page, so I don't want to auto-scroll them since they want to stay where they are.

我需要检测用户是否滚动到页面底部。如果它们在页面的底部，当我向底部添加新内容时，我将自动将它们滚动到新的底部。如果它们不在页面底部，它们正在读取页面上更高的内容，所以我不希望自动滚动它们，因为它们希望保持在当前位置。

How can I detect if a user is scrolled to the bottom of the page or if they have scrolled higher on the page?

如何检测用户是否滚动到页面底部，或者用户是否在页面上滚动得更高?

11 个解决方案

#1

window.onscroll = function(ev) {
    if ((window.innerHeight + window.scrollY) >= document.body.offsetHeight) {
        // you're at the bottom of the page
    }
};

See demo

#2

Updated code for all major browsers support (include IE10 & IE11)

window.onscroll = function(ev) {
    if ((window.innerHeight + window.pageYOffset) >= document.body.offsetHeight) {
        alert("you're at the bottom of the page");
    }
};

The problem with the current accepted answer is that window.scrollY is not available in IE.

当前可接受答案的问题是窗口。IE中没有scrollY。

Here is a quote from mdn regarding scrollY:

以下是mdn对scrollY的引用:

For cross-browser compatibility, use window.pageYOffset instead of window.scrollY.

对于跨浏览器兼容性，请使用窗口。pageYOffset代替window.scrollY。

And a working snippet:

和工作代码片段:

window.onscroll = function(ev) {
    if ((window.innerHeight + window.pageYOffset ) >= document.body.offsetHeight) {
        alert("you're at the bottom of the page");
    }
};

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Note for mac

Based on @Raphaël's comment, there was a problem in mac due to a small offset.
The following updated condition works:

根据@Raphael的评论，mac有一个小的偏移。以下更新后的工作条件:

(window.innerHeight + window.pageYOffset) >= document.body.offsetHeight - 2

I didn't have the chance to test it further, if someone can comment about this specific issue it will be great.

我没有机会进一步测试它，如果有人可以评论这个特定的问题，它将是伟大的。

#3

The accepted answer did not work for me. This did:

公认的答案对我不起作用。这是:

window.onscroll = function(ev) {
    if ((window.innerHeight + window.scrollY) >= document.body.scrollHeight) {
      // you're at the bottom of the page
      console.log("Bottom of page");
    }
};

#4

I was searching for an answer but haven't found an exact one. Here is a pure javascript solution that works with latest Firefox, IE and Chrome at the time of this answer:

我一直在寻找答案，但没有找到确切的答案。这是一个纯javascript的解决方案，与最新的Firefox, IE和Chrome在这个答案的时候使用:

// document.body.scrollTop alone should do the job but that actually works only in case of Chrome.
// With IE and Firefox it also works sometimes (seemingly with very simple pages where you have
// only a <pre> or something like that) but I don't know when. This hack seems to work always.
var scrollTop = (document.documentElement && document.documentElement.scrollTop) || document.body.scrollTop;

// Grodriguez's fix for scrollHeight:
// accounting for cases where html/body are set to height:100%
var scrollHeight = (document.documentElement && document.documentElement.scrollHeight) || document.body.scrollHeight;

// >= is needed because if the horizontal scrollbar is visible then window.innerHeight includes
// it and in that case the left side of the equation is somewhat greater.
var scrolledToBottom = (scrollTop + window.innerHeight) >= scrollHeight;

// As a bonus: how to scroll to the bottom programmatically by keeping the horizontal scrollpos:
// Since window.innerHeight includes the height of the horizontal scrollbar when it is visible
// the correct vertical scrollTop would be
// scrollHeight-window.innerHeight+sizeof(horizontal_scrollbar)
// Since we don't know the visibility/size of the horizontal scrollbar
// we scroll to scrollHeight that exceeds the value of the
// desired scrollTop but it seems to scroll to the bottom with all browsers
// without problems even when the horizontal scrollbar is visible.
var scrollLeft = (document.documentElement && document.documentElement.scrollLeft) || document.body.scrollLeft;
window.scrollTo(scrollLeft, scrollHeight);

#5

I've just started looking at this and the answers here helped me, so thanks for that. I've expanded a little so that the code is safe all the way back to IE7:

我刚开始看这个，这里的答案对我有帮助，谢谢。我已经扩展了一点，这样代码就可以安全地回到IE7:

Hope this proves useful for someone.

希望这对某人有用。

Here, have a Fiddle ;)

这里，有小提琴;)

    <!DOCTYPE html>
<html>
<head>
    <style>
        div {
            height: 100px;
            border-bottom: 1px solid #ddd;
        }

        div:nth-child(even) {
            background: #CCC
        }

        div:nth-child(odd) {
            background: #FFF
        }

    </style>
</head>

<body>
<div></div><div></div><div></div><div></div><div></div><div></div><div></div>
<div></div><div></div><div></div><div></div><div></div><div></div><div></div>
<div></div><div></div><div></div><div></div><div></div><div></div><div></div>
<div></div><div></div><div></div><div></div><div></div><div></div><div></div>
<div></div><div></div><div></div><div></div><div></div><div></div><div></div>
</body>

<script type="text/javascript">
console.log("Doc Height = " + document.body.offsetHeight);
console.log("win Height = " + document.documentElement.clientHeight);
window.onscroll = function (ev) {
    var docHeight = document.body.offsetHeight;
    docHeight = docHeight == undefined ? window.document.documentElement.scrollHeight : docHeight;

    var winheight = window.innerHeight;
    winheight = winheight == undefined ? document.documentElement.clientHeight : winheight;

    var scrollpoint = window.scrollY;
    scrollpoint = scrollpoint == undefined ? window.document.documentElement.scrollTop : scrollpoint;

    if ((scrollpoint + winheight) >= docHeight) {
        alert("you're at the bottom");
    }
};
</script>
</html>

#6

If you're setting height: 100% on some container <div id="wrapper">, then the following code works (tested in Chrome):

如果设置高度:100%在某个容器

，然后下面的代码工作(在Chrome中测试):

var wrapper = document.getElementById('wrapper');

wrapper.onscroll = function (evt) {
  if (wrapper.scrollTop + window.innerHeight >= wrapper.scrollHeight) {
    console.log('reached bottom!');
  }
}

#7

You can look into jquery's infinite scroll:

您可以查看jquery的无限滚动:

http://www.infinite-scroll.com/infinite-scroll-jquery-plugin/

http://www.infinite-scroll.com/infinite-scroll-jquery-plugin/

Which sounds like it does what you're asking for, assuming you're willing to use the jquery library and not hoping for a strict pure JS method.

这听起来就像你所要求的那样，假设你愿意使用jquery库，而不希望使用严格的纯JS方法。

#8

This works

这是

window.onscroll = function() {
    var scrollHeight, totalHeight;
    scrollHeight = document.body.scrollHeight;
    totalHeight = window.scrollY + window.innerHeight;

    if(totalHeight >= scrollHeight)
    {
        console.log("at the bottom");
    }
}

#9

Surprisingly none of the solutions worked for me. I think it's because my css was messed up, and body didn't wrap around all of the content when using height: 100% (don't know why yet). However while looking for a solution I've came up with something well... basically the same, but maybe it's worth to look at - I'm new into programming so sorry if it's doing the same slower, is less supported or something like that...

令人惊讶的是，所有的解决方案对我都不起作用。我认为这是因为我的css搞砸了，而body在使用height: 100%(我还不知道为什么)时并没有涵盖所有内容。然而，在寻找解决方案的时候，我想到了一些很好的东西……基本上是一样的，但也许它值得一看——我对编程很陌生，抱歉如果它做的同样慢，支持较少或者类似的东西……

window.onscroll = function(evt) {
  var check = (Element.getBoundingClientRect().bottom - window.innerHeight <= 0) ? true : false;
  if (check) { console.log("You're at the bottom!"); }
};

#10

$(document).ready(function(){
    $('.NameOfYourDiv').on('scroll',chk_scroll);
});

function chk_scroll(e)
{
    var elem = $(e.currentTarget);
    if (elem[0].scrollHeight - elem.scrollTop() == elem.outerHeight()) 
    {
        alert("scrolled to the bottom");
    }

}

#11

window.onscroll = function(ev) {
    if ((window.innerHeight + Math.ceil(window.pageYOffset)) >= document.body.offsetHeight) {
        alert("you're at the bottom of the page");
    }
};

This Answer will fix edge cases, this is because pageYOffset is double while innerHeight and offsetHeight are long, so when the browser gives you the info, you may be a pixel short. For example: on bottom of the page we have

这个答案将修复边缘情况，这是因为pageYOffset是双倍的，而innerHeight和offsetHeight是长的，所以当浏览器给你信息时，你可能是一个像素的短。例如:在页面的底部

true window.innerHeight = 10.2

真正的窗口。innerHeight = 10.2

true window.pageYOffset = 5.4

真正的窗口。pageYOffset = 5.4

true document.body.offsetHeight = 15.6

真正的document.body。offsetHeight = 15.6

Our calculation then becomes: 10 + 5.4 >= 16 which is false

我们的计算是:10 + 5.4 >= 16，这是错误的

To fix this we can do Math.ceil on the pageYOffset value.

为了解决这个问题，我们可以做数学运算。在pageYOffset值上的ceil。

Hope that helps.

希望有帮助。