我有一个div,只有300像素大,我希望它在页面加载时滚动到内容的底部。这个div有动态添加的内容,需要一直向下滚动。现在如果用户决定向上滚动,我不希望它跳回底部,直到用户再次向下滚动

是否有可能有一个div,将保持滚动到底部,除非用户向上滚动,当用户滚动回底部时,它需要保持自己在底部,即使添加了新的动态内容。我该怎么做呢。


当前回答

这里有一个基于Ryan Hunt博客文章的解决方案。它取决于overflow-anchor CSS属性,该属性将滚动位置固定在滚动内容底部的元素上。

function addMessage() { const $message = document.createElement('div'); $message.className = 'message'; $message.innerText = `Random number = ${Math.ceil(Math.random() * 1000)}`; $messages.insertBefore($message, $anchor); // Trigger the scroll pinning when the scroller overflows if (!overflowing) { overflowing = isOverflowing($scroller); $scroller.scrollTop = $scroller.scrollHeight; } } function isOverflowing($el) { return $el.scrollHeight > $el.clientHeight; } const $scroller = document.querySelector('.scroller'); const $messages = document.querySelector('.messages'); const $anchor = document.querySelector('.anchor'); let overflowing = false; setInterval(addMessage, 1000); .scroller { overflow: auto; height: 90vh; max-height: 11em; background: #555; } .messages > * { overflow-anchor: none; } .anchor { overflow-anchor: auto; height: 1px; } .message { margin: .3em; padding: .5em; background: #eee; } <section class="scroller"> <div class="messages"> <div class="anchor"></div> </div> </section>

注意,overflow-anchor目前在Safari中不起作用。

其他回答

$('#div1').scrollTop($('#div1')[0].scrollHeight);

Or animated:

$("#div1").animate({ scrollTop: $('#div1')[0].scrollHeight}, 1000);

我刚刚实现了这个,也许你可以用我的方法。

假设我们有以下HTML:

<div id="out" style="overflow:auto"></div>

然后我们可以检查它是否滚动到底部:

var out = document.getElementById("out");
// allow 1px inaccuracy by adding 1
var isScrolledToBottom = out.scrollHeight - out.clientHeight <= out.scrollTop + 1;

scrollHeight gives you the height of the element, including any non visible area due to overflow. clientHeight gives you the CSS height or said in another way, the actual height of the element. Both methods returns the height without margin, so you needn't worry about that. scrollTop gives you the position of the vertical scroll. 0 is top and max is the scrollHeight of the element minus the element height itself. When using the scrollbar it can be difficult (it was in Chrome for me) to get the scrollbar all the way down to the bottom. so I threw in a 1px inaccuracy. So isScrolledToBottom will be true even if the scrollbar is 1px from the bottom. You can set this to whatever feels right to you.

然后,只需将元素的scrollTop设置为底部即可。

if(isScrolledToBottom)
    out.scrollTop = out.scrollHeight - out.clientHeight;

我已经为你做了一个小提琴的概念:http://jsfiddle.net/dotnetCarpenter/KpM5j/

编辑: 增加了代码片段以澄清当isScrolledToBottom为真时。

Stick scrollbar to bottom const out = document.getElementById("out") let c = 0 setInterval(function() { // allow 1px inaccuracy by adding 1 const isScrolledToBottom = out.scrollHeight - out.clientHeight <= out.scrollTop + 1 const newElement = document.createElement("div") newElement.textContent = format(c++, 'Bottom position:', out.scrollHeight - out.clientHeight, 'Scroll position:', out.scrollTop) out.appendChild(newElement) // scroll to bottom if isScrolledToBottom is true if (isScrolledToBottom) { out.scrollTop = out.scrollHeight - out.clientHeight } }, 500) function format () { return Array.prototype.slice.call(arguments).join(' ') } #out { height: 100px; } <div id="out" style="overflow:auto"></div> <p>To be clear: We want the scrollbar to stick to the bottom if we have scrolled all the way down. If we scroll up, then we don't want the content to move. </p>

与Bootstrap 5:

< span style=" font - family:宋体;max-height: 300 px;" > < div > <!——你这里的内容——> < / div > < / div >

$('#yourDiv').scrollTop($('#yourDiv')[0].scrollHeight);

现场演示:http://jsfiddle.net/KGfG2/

我设法把它修好了。诀窍是计算:(a)当前div用户滚动位置和(b) div滚动高度,都是在附加新元素之前。

如果a === b,则在追加新元素之前就知道用户位于底部。

    let div = document.querySelector('div.scrollableBox');

    let span = document.createElement('span');
    span.textContent = 'Hello';

    let divCurrentUserScrollPosition = div.scrollTop + div.offsetHeight;
    let divScrollHeight = div.scrollHeight;

    // We have the current scroll positions saved in
    // variables, so now we can append the new element.
    div.append(span);

    
    if ((divScrollHeight === divCurrentUserScrollPosition)) {
        // Scroll to bottom of div
        div.scrollTo({ left: 0, top: div.scrollHeight });
    }