菜鳥可以學會的使用js的三種方式
通過id使用js事件
<!DOCTYPE html>
<html>
<body>
<p>該執行個體聲明一個函數，函數調用時在 id="demo" 的元素上輸出 "Hello World" 。</p>
<p id="demo2"></p>
<script>
function myFunction() {
document.getElementById("demo2").innerHTML = "Hello World!";
}
myFunction();
</script>
</body>
</html> <!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script>
function myFunction(){
alert("你好，我是一個警告框！");
}
</script>
</head>
<body>
<input type="button" onclick="myFunction()" value="顯示警告框" />
</body>
</html> <html>
<head>
<script type="text/javascript">
function getElements()
{
var x=document.getElementsByTagName("input");
alert(x.length);
}
</script>
</head>
<body>
<input name="myInput" type="text" size="20" /><br />
<input name="myInput" type="text" size="20" /><br />
<input name="myInput" type="text" size="20" /><br />
<br />
<input type="button" onclick="getElements()"
value="How many input elements?" />
</body>
</html> ![一個小小的移動web版音樂播放器[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)