通过script嵌入
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
</body>
<script type="text/javascript">
document.write("使用JavaScript脚本语言循环输出hello world!")
for(var i = 0; i < 3; i++){
document.write("<h1>hello world!</h1>")
}
</script>
</html>在html直接引入
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<input type="button" value="弹出消息框" onclick="alert('hello world!')"/>
</body>
</html>引入外部js文件
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
</body>
<script type="text/javascript" src="js/hello.js"></script>
</html>外部JS文件：hello.js
document.write("使用JavaScript脚本语言循环输出hello world!")
for(var i = 0; i < 3; i++){
document.write("<h1>hello world!</h1>");
}作业：图片排版
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<script type="text/javascript" src="js/hello2.js"></script>
<link href="css/style.css" type="text/css" rel="stylesheet"/>
</head>
<body>
</body>
</html>1.引入外部JS文件：hello2.js
document.write('<ul>');
for(var i =1; i<= 6; i++){
document.write("<li><a href=''><img src='img/" + i + ".webp'/></a></li>");
}
document.write('</ul>');2.再引入CSS文件：style.css
*{
margin: 0;
padding: 0;
}
body{
background-color: black;
}
ul{
list-style: none;
margin: 0 auto;
text-align: center;
}
ul li{
display: inline-block;
width: 186px;
height: 248px;
margin-left: 10px;
}
ul>li>a>img{
width: 186px;
height: 248px;
}图片文件：
1.webp
2.webp
3.webp
4.webp
5.webp
6.webp
