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JavaScript Usage
HTML? ????? <script> ??? </script>
????? HTML ???? <body> ??? ??? ? ????.
<script> ??
JavaScript? HTML ???? ????? <script>
<script> ? </script>? JavaScript? ?? ??? ? ??? ?????.
<script>? </script> ???? JavaScript? ???? ????.
<script> alert("我的第一個 JavaScript"); </script>
?? ??? ??? ??? ????. ????? <script> ="text/javascript" ??? JavaScript ??? ???? ????? ?? ?????. ? ?? ???? ????. JavaScript? HTML5?? ??? ?? ?? ????? ?? ???? ?????.
<body>
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> </head> <body> <p> JavaScript 能夠直接寫入 HTML 輸出流中: </p> <script> document.write("<h1>This is a title</h1>"); document.write("<p>This is a paragraph</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>? JavaScript
HTML ???? ????? ????? ?? ? ????.
????? HTML? <body> ?? <head> ??? ?? ? ????.
???? ?? ??? ??? <head> ???? ??? ??? ???? ????. ?? ?? ??? ??? ???? ?? ??? ??? ??? ? ????.
<head>
? JavaScript ?? ? ???? HTML ???? <head> ??? JavaScript ??? ?????.
??? ???? ? ??? ?????.
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <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> . ??.
??? ???? ? ??? ?????.
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> </head> <body> <h1>My first web</h1> <p id="demo">This is a paragraph</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 ??? ?????.
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> </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>