?????? ???
JavaScript ???
HTML? ????? <script> ??? </script>
????? HTML ???? <body> ??? ??? ? ????.
<script> ??
JavaScript? HTML ???? ????? <script> ??? ?????.
<script> ? </script>? JavaScript? ?? ??? ? ??? ?????.
<script>? </script> ??? ?? ??? JavaScript? ???? ????.
<script>
alert("My first JavaScript");
</script>
?? ??? ???? ???. ????? <script>? </script> ??? JavaScript ??? ???? ????? ?? ?????.
<body>
? ?? JavaScript? ???? ??? ? HTML? <body>? ???? ???.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)(php.cn)</title>
</head>
<body>
<p>
JavaScript 能夠直接寫入 HTML 輸出流中：
</p>
<script>
document.write("<h1>這是一個標(biāo)題</h1>");
document.write("<p>這是一個段落。</p>");
</script>
<p>
您只能在 HTML 輸出流中使用 <strong>document.write</strong>。
如果您在文檔已加載后使用它（比如在函數(shù)中），會覆蓋整個文檔。
</p>
</body>
</html>????? ??? ???
JavaScript ?? ? ???
? ??? JavaScript ?? ???? ??? ? ?????.
????? ???? ??? ???? ? ???? ??? ? ??? ???? ???.
??? ?????? ??? ??? ??? ??? ??? ??? ? ????.
<head> ?? <body>
HTML ??? ????? ????? ?? ? ????.
????? HTML? <body> ???? <head> ??? ?? ? ????.
???? ?? ??? ??? <head> ???? ??? ??? ???? ????. ?? ?? ??? ??? ???? ?? ??? ??? ??? ? ????.
<head>
? JavaScript ?? ? ???? HTML ???? <head> ??? JavaScript ??? ?????.
??? ???? ? ??? ?????.
Instance
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)(php.cn)</title>
<script>
function myFunction(){
document.getElementById("demo").innerHTML="我的第一個 JavaScript 函數(shù)";
}
</script>
</head>
<body>
<h1>我的 Web 頁面</h1>
<p id="demo">一個段落。</p>
<button type="button" onclick="myFunction()">點擊這里</button>
</body>
</html>????? ???? ??? ???.
<body> JavaScript ??
HTML ???? <body> ??? JavaScript ??? ?????.
??? ???? ? ??? ?????.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>PHP中文網(wǎng)(php.cn)</title>
</head>
<body>
<h1>我的第一個 Web 頁面</h1>
<p id="demo">一個段落。</p>
<button type="button" onclick="myFunction()">點擊這里</button>
<script>
function myFunction(){
document.getElementById("demo").innerHTML="我的第一個 JavaScript 函數(shù)";
}
</script>
</body>
</html>????? ???? ??? ???
?? JavaScript
????? ?? ??? ??? ?? ????. ?? ???? ?? ? ????? ???? ??? ???? ??? ????.
?? JavaScript ??? ?? ???? .js???.
?? ??? ???? ?? ?? <script> ??? "src" ??? .js ??? ?????.
Example
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>PHP中文網(wǎng)（php.cn）</title> </head> <body> <h1>我的 Web 頁面</h1> <p id="demo">一個段落。</p> <button type="button" onclick="myFunction()">點擊這里</button> <p><b>注釋：</b>myFunction 保存在名為 "myScript.js" 的外部文件中。</p> <script src="myScript.js"></script> </body> </html>
????? < head> ?? <body? ?? ?? ??>? <script>
myScript.js ?? ??? ??? ????.
function myFunction(){
document.getElementById("demo").innerHTML="My first JavaScript function";}
?? : ?? ?????? <script> ??? ??? ? ????.
