HTML script

JavaScript makes HTML pages more dynamic and interactive.

Online example

Insert a script
How to insert a script into an HTML document.

Instance

<!DOCTYPE html>
<html>
<head> 
<meta charset="utf-8"> 
<title>php中文网(php.cn)</title> 
</head>
<body>

<script>
document.write("Hello World!")
</script> 

</body>
</html>

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Use the <noscript> tag
How to deal with browsers that do not support scripts or have scripts disabled.

Instance

<!DOCTYPE html>
<html>
<head> 
<meta charset="utf-8"> 
<title>php中文网(php.cn)</title> 
</head> 
<body>

<script>
document.write("Hello World!")
</script>
<noscript>抱歉，你的浏览器不支持 JavaScript!</noscript>

<p>不支持 JavaScript 的浏览器会使用 <noscript> 元素中定义的内容（文本）来替代。</p>
 
</body>
</html>

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HTML <script> tag

JavaScript is most commonly used for image manipulation, form validation, and dynamic content updating.

The following script will output "Hello World!" to the browser:

Example

<!DOCTYPE html>
<html>
<head> 
<meta charset="utf-8"> 
<title>php中文网(php.cn)</title> 
</head> 
<body>

<script>
document.write("Hello World!")
</script>
<noscript>抱歉，你的浏览器不支持 JavaScript!</noscript>

<p>不支持 JavaScript 的浏览器会使用 <noscript> 元素中定义的内容（文本）来替代。</p>
 
</body>
</html>

Running Example»

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Tip: To learn more about Javascript tutorials, please check out JavaScript Tutorials!

HTML<noscript> tag

Only when the browser does not support scripts or scripts are disabled, the content in the <noscript> element will be displayed:

Example

<!DOCTYPE html>
<html>
<head> 
<meta charset="utf-8"> 
<title>php中文网(php.cn)</title> 
</head> 
<body>

<script>
document.write("Hello World!")
</script>
<noscript>抱歉，你的浏览器不支持 JavaScript!</noscript>

<p>不支持 JavaScript 的浏览器会使用 <noscript> 元素中定义的内容（文本）来替代。</p>
 
</body>
</html>

Run instance»

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JavaScript experience (from this site's javascript tutorial)

JavaScript Example Code

Example

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>php中文网(php.cn)</title>
</head>
<body>
	
<p>
JavaScript 能够直接写入 HTML 输出流中：
</p>
<script>
document.write("<h1>这是一个标题</h1>");
document.write("<p>这是一个段落。</p>");
</script>
<p>
您只能在 HTML 输出流中使用 <strong>document.write</strong>。
如果您在文档已加载后使用它（比如在函数中），会覆盖整个文档。
</p>
	
</body>
</html>

Run Example»

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Instance

<!DOCTYPE html>
<html>
<head> 
<meta charset="utf-8"> 
<title>php中文网(php.cn)</title> 
</head>
<body>

<h1>我的第一个 JavaScript </h1>

<p id="demo">
JavaScript 可以触发事件，就像按钮点击。</p>

<script>
function myFunction()
{
	document.getElementById("demo").innerHTML="Hello JavaScript!";
}
</script>

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Instance

<!DOCTYPE html>
<html>
<head> 
<meta charset="utf-8"> 
<title>php中文网(php.cn)</title> 
</head>
<body>
	
<h1>我的第一段 JavaScript</h1>
<p id="demo">
JavaScript 能改变 HTML 元素的样式。
</p>
<script>
function myFunction()
{
	x=document.getElementById("demo") // 找到元素
	x.style.color="#ff0000";          // 改变样式
}
</script>
<button type="button" onclick="myFunction()">点击这里</button>
	
</body>
</html>

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