本节开始介绍javascript在html页面中的运用。
(1)link样式表的动态绑定:(http://files.cnblogs.com/files/MenAngel/text04.zip)
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title>示例9.1</title>
<link id="olink" href="css/01.css" rel="stylesheet" />
<script>
function tored() {
var alink = document.getElementById('olink');
alink.href = 'css/01.css';
}
function toblue() {
var alink = document.getElementById('olink');
alink.href = 'css/02.css';
}
</script>
</head>
<body>
<input type="button" value="red" onclick="tored()"/>
<input type="button" value="blue" onclick="toblue()" />
<div></div>
</body>
</html>
(2)js中参数的传递
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title>示例9.2</title>
<style>
#div1 {
width:200px;
height:200px;
background-color:red;
}
</style>
<script>
function tobianshe(yanshe) {
var odiv = document.getElementById('div1');
odiv.style.backgroundColor = yanshe;
}/*
function toblue() {
var odiv = document.getElementById('div1');
odiv.style.backgroundColor = 'blue';
}
function toyellow() {
var odiv = document.getElementById('div1');
odiv.style.backgroundColor = 'yellow';
}
function togreen() {
var odiv = document.getElementById('div1');
odiv.style.backgroundColor = 'green';
}*/
</script>
</head>
<body>
<input type="button" value="变蓝" onclick="tobianshe('blue')"/>
<input type="button" value="变黄" onclick="tobianshe('yellow')"/>
<input type="button" value="变绿" onclick="tobianshe('green')"/>
<div id="div1">
</div>
</body>
</html>
(3)显示和隐藏元素:
<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>示例9.3</title>
<style>
#div1{
width:200px;
height:200px;
background:#CCC;
display:none;
}
</style>
<script>
function showHide()
{
var oDiv = document.getElementById('div1');
if (oDiv.style.display == 'block') {
oDiv.style.display = 'none';
}
else{
oDiv.style.display = 'block';
}
}
</script>
</head> <body>
<input type="button" value="显示隐藏" onclick="showHide()" />
<div id="div1" >
</div>
</body>
</html>
(4)js中选取成组元素:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title>示例9.4</title>
<script>
<!--在页面运行时自调用，如果设置事件，需要给函数加上函数名-->
window.onload=function(){
var aDiv = document.getElementsByTagName('div');
var cDiv = document.getElementsByClassName('a');
alert("元素的个数为:"+cDiv.length);
}
</script>
</head>
<body>
<div></div>
<div class="a"></div>
<div></div>
<div></div>
<div class="a"></div>
<div></div>
<div></div>
<div></div>
<div class="a"></div>
<div></div>
<div></div>
</body>
</html>
(5)js中的定时器:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title>示例9.5</title>
<script>
window.onload = function (){
var obtn1 = document.getElementById('btn1');
var obtn2 = document.getElementById('btn2');
var timer = null;
obtn1.onclick = function () {
<!--setInterval的返回值是一个timer类型-->
timer= setInterval(function () { alert('基友节');},5000);//每5秒执行一次
}
obtn2.onclick = function () {
clearInterval(timer);
}
}
</script>
</head>
<body>
<input type="button" value="开启" id="btn1"/>
<input type="button" value="关闭" id="btn2"/>
</body>
</html>
