我有一个滚动的div,我想有一个事件,当我点击它,它将迫使这个div滚动查看里面的一个元素。 我这样写它的JavasSript:
document.getElementById(chr).scrollIntoView(true);
但这在滚动div本身的同时滚动整个页面。 如何解决这个问题?
我想这样说: MyContainerDiv.getElementById(杆).scrollIntoView(真正的);
我有一个滚动的div,我想有一个事件,当我点击它,它将迫使这个div滚动查看里面的一个元素。 我这样写它的JavasSript:
document.getElementById(chr).scrollIntoView(true);
但这在滚动div本身的同时滚动整个页面。 如何解决这个问题?
我想这样说: MyContainerDiv.getElementById(杆).scrollIntoView(真正的);
当前回答
只有在需要的时候,你才能使用scrollIfNeeded函数将一个元素滚动到div的视图中:
function scrollIfNeeded(element, container) { if (element.offsetTop < container.scrollTop) { container.scrollTop = element.offsetTop; } else { const offsetBottom = element.offsetTop + element.offsetHeight; const scrollBottom = container.scrollTop + container.offsetHeight; if (offsetBottom > scrollBottom) { container.scrollTop = offsetBottom - container.offsetHeight; } } } document.getElementById('btn').addEventListener('click', ev => { ev.preventDefault(); scrollIfNeeded(document.getElementById('goose'), document.getElementById('container')); }); .scrollContainer { overflow-y: auto; max-height: 100px; position: relative; border: 1px solid red; width: 120px; } body { padding: 10px; } .box { margin: 5px; background-color: yellow; height: 25px; display: flex; align-items: center; justify-content: center; } #goose { background-color: lime; } <div id="container" class="scrollContainer"> <div class="box">duck</div> <div class="box">duck</div> <div class="box">duck</div> <div class="box">duck</div> <div class="box">duck</div> <div class="box">duck</div> <div class="box">duck</div> <div class="box">duck</div> <div id="goose" class="box">goose</div> <div class="box">duck</div> <div class="box">duck</div> <div class="box">duck</div> <div class="box">duck</div> </div> <button id="btn">scroll to goose</button>
其他回答
另一个使用jQuery和动画的例子。
var container = $('#container');
var element = $('#element');
container.animate({
scrollTop: container.scrollTop = container.scrollTop() + element.offset().top - container.offset().top
}, {
duration: 1000,
specialEasing: {
width: 'linear',
height: 'easeOutBounce'
},
complete: function (e) {
console.log("animation completed");
}
});
我需要滚动页面上的动态加载元素,所以我的解决方案有点复杂。
这将适用于静态元素,这些静态元素不是惰性加载数据,也不是动态加载数据。
const smoothScrollElement = async (selector: string, scrollBy = 12, prevCurrPos = 0) => {
const wait = (timeout: number) => new Promise(resolve => setTimeout(resolve, timeout));
const el = document.querySelector(selector) as HTMLElement;
let positionToScrollTo = el.scrollHeight;
let currentPosition = Math.floor(el.scrollTop) || 0;
let pageYOffset = (el.clientHeight + currentPosition);
if (positionToScrollTo == pageYOffset) {
await wait(1000);
}
if ((prevCurrPos > 0 && currentPosition <= prevCurrPos) !== true) {
setTimeout(async () => {
el.scrollBy(0, scrollBy);
await smoothScrollElement(selector, scrollBy, currentPosition);
}, scrollBy);
}
};
用户动画滚动
下面是一个如何在没有JQuery的情况下以编程方式横向滚动<div>的示例。要垂直滚动,可以将JavaScript对scrollLeft的写入替换为scrollTop。
JSFiddle
https://jsfiddle.net/fNPvf/38536/
HTML
<!-- Left Button. -->
<div style="float:left;">
<!-- (1) Whilst it's pressed, increment the scroll. When we release, clear the timer to stop recursive scroll calls. -->
<input type="button" value="«" style="height: 100px;" onmousedown="scroll('scroller',3, 10);" onmouseup="clearTimeout(TIMER_SCROLL);"/>
</div>
<!-- Contents to scroll. -->
<div id="scroller" style="float: left; width: 100px; height: 100px; overflow: hidden;">
<!-- <3 -->
<img src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.png?v=9c558ec15d8a" alt="image large" style="height: 100px" />
</div>
<!-- Right Button. -->
<div style="float:left;">
<!-- As (1). (Use a negative value of 'd' to decrease the scroll.) -->
<input type="button" value="»" style="height: 100px;" onmousedown="scroll('scroller',-3, 10);" onmouseup="clearTimeout(TIMER_SCROLL);"/>
</div>
JavaScript
// Declare the Shared Timer.
var TIMER_SCROLL;
/**
Scroll function.
@param id Unique id of element to scroll.
@param d Amount of pixels to scroll per sleep.
@param del Size of the sleep (ms).*/
function scroll(id, d, del){
// Scroll the element.
document.getElementById(id).scrollLeft += d;
// Perform a delay before recursing this function again.
TIMER_SCROLL = setTimeout("scroll('"+id+"',"+d+", "+del+");", del);
}
这要归功于Dux。
自动动画滚动
此外,这里还有用于将<div>完全向左和向右滚动的函数。这里我们唯一改变的是,在再次递归调用滚动之前,检查是否已经使用了滚动的完整扩展。
JSFiddle
https://jsfiddle.net/0nLc2fhh/1/
HTML
<!-- Left Button. -->
<div style="float:left;">
<!-- (1) Whilst it's pressed, increment the scroll. When we release, clear the timer to stop recursive scroll calls. -->
<input type="button" value="«" style="height: 100px;" onclick="scrollFullyLeft('scroller',3, 10);"/>
</div>
<!-- Contents to scroll. -->
<div id="scroller" style="float: left; width: 100px; height: 100px; overflow: hidden;">
<!-- <3 -->
<img src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.png?v=9c558ec15d8a" alt="image large" style="height: 100px" />
</div>
<!-- Right Button. -->
<div style="float:left;">
<!-- As (1). (Use a negative value of 'd' to decrease the scroll.) -->
<input type="button" value="»" style="height: 100px;" onclick="scrollFullyRight('scroller',3, 10);"/>
</div>
JavaScript
// Declare the Shared Timer.
var TIMER_SCROLL;
/**
Scroll fully left function; completely scrolls a <div> to the left, as far as it will go.
@param id Unique id of element to scroll.
@param d Amount of pixels to scroll per sleep.
@param del Size of the sleep (ms).*/
function scrollFullyLeft(id, d, del){
// Fetch the element.
var el = document.getElementById(id);
// Scroll the element.
el.scrollLeft += d;
// Have we not finished scrolling yet?
if(el.scrollLeft < (el.scrollWidth - el.clientWidth)) {
TIMER_SCROLL = setTimeout("scrollFullyLeft('"+id+"',"+d+", "+del+");", del);
}
}
/**
Scroll fully right function; completely scrolls a <div> to the right, as far as it will go.
@param id Unique id of element to scroll.
@param d Amount of pixels to scroll per sleep.
@param del Size of the sleep (ms).*/
function scrollFullyRight(id, d, del){
// Fetch the element.
var el = document.getElementById(id);
// Scroll the element.
el.scrollLeft -= d;
// Have we not finished scrolling yet?
if(el.scrollLeft > 0) {
TIMER_SCROLL = setTimeout("scrollFullyRight('"+id+"',"+d+", "+del+");", del);
}
}
你需要获得你想要滚动到视图中的元素的顶部偏移量,相对于它的父元素(滚动div容器):
var myElement = document.getElementById('element_within_div');
var topPos = myElement.offsetTop;
变量topPos现在被设置为滚动div的顶部与您希望可见的元素之间的距离(以像素为单位)。
现在我们使用scrollTop命令让div滚动到那个位置:
document.getElementById('scrolling_div').scrollTop = topPos;
如果你正在使用原型JS框架,你会做同样的事情:
var posArray = $('element_within_div').positionedOffset();
$('scrolling_div').scrollTop = posArray[1];
同样,这将滚动div,以便您希望看到的元素恰好位于顶部(如果不可能,则尽可能向下滚动,使其可见)。
这是一个简单的纯JavaScript解决方案,适用于目标数字(值为scrollTop),目标DOM元素,或一些特殊的字符串情况:
/**
* target - target to scroll to (DOM element, scrollTop Number, 'top', or 'bottom'
* containerEl - DOM element for the container with scrollbars
*/
var scrollToTarget = function(target, containerEl) {
// Moved up here for readability:
var isElement = target && target.nodeType === 1,
isNumber = Object.prototype.toString.call(target) === '[object Number]';
if (isElement) {
containerEl.scrollTop = target.offsetTop;
} else if (isNumber) {
containerEl.scrollTop = target;
} else if (target === 'bottom') {
containerEl.scrollTop = containerEl.scrollHeight - containerEl.offsetHeight;
} else if (target === 'top') {
containerEl.scrollTop = 0;
}
};
下面是一些用法的例子:
// Scroll to the top
var scrollableDiv = document.getElementById('scrollable_div');
scrollToTarget('top', scrollableDiv);
or
// Scroll to 200px from the top
var scrollableDiv = document.getElementById('scrollable_div');
scrollToTarget(200, scrollableDiv);
or
// Scroll to targetElement
var scrollableDiv = document.getElementById('scrollable_div');
var targetElement= document.getElementById('target_element');
scrollToTarget(targetElement, scrollableDiv);