onscroll 事件
JavaScript基础 2022-06-08 12:02:37小码哥的IT人生shichen
onscroll 事件
实例
在滚动 <div> 元素时执行 JavaScript：
<div onscroll="myFunction()">
完整实例：
<!DOCTYPE html>
<html>
<head>
<style>
div {
border: 1px solid black;
width: 200px;
height: 100px;
overflow: scroll;
}
</style>
</head>
<body>
<p>请试试 div 中的滚动条。</p>
<div onscroll="myFunction()">In my younger and more vulnerable years my father gave me some advice that I've been turning over in my mind ever since.
<br><br>
'Whenever you feel like criticizing anyone,' he told me, just remember that all the people in this world haven't had the advantages that you've had.'</div>
<p>Scrolled <span id="demo">0</span> times.</p>
<script>
var x = 0;
function myFunction() {
document.getElementById("demo").innerHTML = x += 1;
}
</script>
</body>
</html>
可以使用本站在线JavaScript测试工具测试上述代码运行效果：http://www.phpcodeweb.com/runjs.html
浏览器支持
| 事件 | Chrome | IE | Firefox | Safari | Opera |
|---|---|---|---|---|---|
| onscroll | 支持 | 支持 | 支持 | 支持 | 支持 |
语法
在 HTML 中：
<element onscroll="myScript">
完整实例：
<!DOCTYPE html>
<html>
<head>
<style>
div {
border: 1px solid black;
width: 200px;
height: 100px;
overflow: scroll;
}
</style>
</head>
<body>
<p>请试试 div 中的滚动条。</p>
<div onscroll="myFunction()">In my younger and more vulnerable years my father gave me some advice that I've been turning over in my mind ever since.
<br><br>
'Whenever you feel like criticizing anyone,' he told me, just remember that all the people in this world haven't had the advantages that you've had.'</div>
<p id="demo"></p>
<script>
function myFunction() {
document.getElementById("demo").innerHTML = "You scrolled in div.";
}
</script>
</body>
</html>
可以使用本站在线JavaScript测试工具测试上述代码运行效果：http://www.phpcodeweb.com/runjs.html
在 JavaScript 中：
object.onscroll = function(){myScript};
完整实例：
<!DOCTYPE html>
<html>
<head>
<style>
div {
border: 1px solid black;
width: 200px;
height: 100px;
overflow: scroll;
}
</style>
</head>
<body>
<p>本例使用 HTML DOM 将 "onscroll" 事件分配给 div 元素。</p>
<p>请试试 div 中的滚动条</p>
<div id="myDIV">In my younger and more vulnerable years my father gave me some advice that I've been turning over in my mind ever since.
<br><br>
'Whenever you feel like criticizing anyone,' he told me, just remember that all the people in this world haven't had the advantages that you've had.'</div>
<p id="demo"></p>
<script>
document.getElementById("myDIV").onscroll = function() {myFunction()};
function myFunction() {
document.getElementById("demo").innerHTML = "You scrolled in div.";
}
</script>
</body>
</html>
可以使用本站在线JavaScript测试工具测试上述代码运行效果：http://www.phpcodeweb.com/runjs.html
在 JavaScript 中，使用 addEventListener() 方法：
object.addEventListener("scroll", myScript);
完整实例：
<!DOCTYPE html>
<html>
<head>
<style>
div {
border: 1px solid black;
width: 200px;
height: 100px;
overflow: scroll;
}
</style>
</head>
<body>
<p>本例使用 addEventListener() 方法将 "scroll" 事件附加到 div 元素。</p>
<p>请试试 div 中的滚动条</p>
<div id="myDIV">In my younger and more vulnerable years my father gave me some advice that I've been turning over in my mind ever since.
<br><br>
'Whenever you feel like criticizing anyone,' he told me, just remember that all the people in this world haven't had the advantages that you've had.'</div>
<p id="demo"></p>
<script>
document.getElementById("myDIV").addEventListener("scroll", myFunction);
function myFunction() {
document.getElementById("demo").innerHTML = "You scrolled in div.";
}
</script>
</body>
</html>
可以使用本站在线JavaScript测试工具测试上述代码运行效果：http://www.phpcodeweb.com/runjs.html
注释：Internet Explorer 8 或更早的版本不支持 addEventListener() 方法。
技术细节
| 冒泡： | 不支持 |
|---|---|
| 可取消： | 不支持 |
| 事件类型： | 如果从用户界面生成，UiEvent。否则 Event。 |
| 支持的 HTML 标签： | <address>, <blockquote>, <body>, <caption>, <center>, <dd>, <dir>, <div>, <dl>, <dt>, <fieldset>, <form>, <h1> to <h6>, <html>, <li>, <menu>, <object>, <ol>, <p>, <pre>, <select>, <tbody>, <textarea>, <tfoot>, <thead>, <ul> |
| DOM 版本： | Level 2 Events |
更多实例
示例代码：
在不同滚动位置的类名之间切换 - 当用户从页面顶部向下滚动 50 像素时，类名 "test" 将被添加到元素中（再次向上滚动时将被删除）。
window.onscroll = function() {myFunction()};
function myFunction() {
if (document.body.scrollTop > 50 || document.documentElement.scrollTop > 50) {
document.getElementById("myP").className = "test";
} else {
document.getElementById("myP").className = "";
}
}
完整实例：
<!DOCTYPE html>
<html>
<head>
<style>
.test {
background-color: yellow;
}
</style>
</head>
<body style="height:1500px">
<p>向下滚动此页面</p>
<p id="myP" style="position:fixed">当您从该页面顶部滚动 50 像素后，将类 "test"（黄色背景色）添加到该段落。再次向上滚动以删除类。</p>
<script>
window.onscroll = function() {myFunction()};
function myFunction() {
if (document.body.scrollTop > 50 || document.documentElement.scrollTop > 50) {
document.getElementById("myP").className = "test";
} else {
document.getElementById("myP").className = "";
}
}
</script>
</body>
</html>
可以使用本站在线JavaScript测试工具测试上述代码运行效果：http://www.phpcodeweb.com/runjs.html
示例代码：
当用户从页面顶部向下滚动 350 像素时滑入元素（添加 slideUp 类）：
window.onscroll = function() {myFunction()};
function myFunction() {
if (document.body.scrollTop > 350 || document.documentElement.scrollTop > 350) {
document.getElementById("myImg").className = "slideUp";
}
}
完整实例：
<!DOCTYPE html>
<html>
<head>
<style>
.slideUp {
animation-name: slideUp;
-webkit-animation-name: slideUp;
animation-duration: 1s;
-webkit-animation-duration: 1s;
visibility: visible;
}
@keyframes slideUp {
0% {
opacity: 0;
-webkit-transform: translateY(70%);
}
100% {
opacity: 1;
-webkit-transform: translateY(0%);
}
}
@-webkit-keyframes slideUp {
0% {
opacity: 0;
-webkit-transform: translateY(70%);
}
100% {
opacity: 1;
-webkit-transform: translateY(0%);
}
}
body {height:1500px;}
.col-1 {float:left}
.col-2 {float:left;padding-left:25px;}
img {width:180px;height:100px;visibility:hidden;}
hr {margin-top:400px;}
</style>
</head>
<body>
<p>请向下滚动此页面</p>
<p>当您从顶部滚动 350 像素时，图像将滑入。</p>
<hr>
<div class="col-1">
<img id="myImg" src="/i/photo/tulip.jpg" width="300" height="300">
</div>
<div class="col-2">
Just some text..
</div>
<script>
window.onscroll = function() {myFunction()};
function myFunction() {
if (document.body.scrollTop > 350 || document.documentElement.scrollTop > 350) {
document.getElementById("myImg").className = "slideUp";
}
}
</script>
</body>
</html>
可以使用本站在线JavaScript测试工具测试上述代码运行效果：http://www.phpcodeweb.com/runjs.html
