发布于 2017-01-19 00:25:30 | 129 次阅读 | 评论: 0 | 来源: 网友投递
这里有新鲜出炉的Javascript教程，程序狗速度看过来！
JavaScript客户端脚本语言
Javascript 是一种由Netscape的LiveScript发展而来的原型化继承的基于对象的动态类型的区分大小写的客户端脚本语言，主要目的是为了解决服务器端语言，比如Perl，遗留的速度问题，为客户提供更流畅的浏览效果。
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>图片旋转效果</title>
<meta http-equiv="content-type" content="text/html;charset=gb2312">
<!--把下面代码加到<head>与</head>之间-->
<style type="text/css">
ul{padding:0 15px;}
ul li{padding-bottom:15px;border-bottom:1px dashed #EEE;}
.caption{padding:15px 0 5px;}
.caption input{margin-right:10px;padding:0 10px;}
</style>
<script type="text/javascript">
/*
* www.byzuo.com
* ok!: MSIE 6, 7, 8, Firefox 3.6, chrome 4, Safari 4, Opera 10
* o 旋转图片ID;
* p 选择旋转方向，固定值为'left'或'right';
*/
function rotate(o,p){
var img = document.getElementById(o);
if(!img || !p) return false;
var n = img.getAttribute('step');
if(n== null) n=0;
if(p=='right'){
(n==3)? n=0:n++;
}else if(p=='left'){
(n==0)? n=3:n--;
}
img.setAttribute('step',n);
//MSIE
if(document.all) {
img.style.filter = 'progid:DXImageTransform.Microsoft.BasicImage(rotation='+ n +')';
//HACK FOR MSIE 8
switch(n){
case 0:
imgimg.parentNode.style.height = img.height;
break;
case 1:
imgimg.parentNode.style.height = img.width;
break;
case 2:
imgimg.parentNode.style.height = img.height;
break;
case 3:
imgimg.parentNode.style.height = img.width;
break;
}
//DOM
}else{
var c = document.getElementById('canvas_'+o);
if(c== null){
img.style.visibility = 'hidden';
img.style.position = 'absolute';
c = document.createElement('canvas');
c.setAttribute("id",'canvas_'+o);
img.parentNode.appendChild(c);
}
var ccanvasContext = c.getContext('2d');
switch(n) {
default :
case 0 :
c.setAttribute('width', img.width);
c.setAttribute('height', img.height);
canvasContext.rotate(0 * Math.PI / 180);
canvasContext.drawImage(img, 0, 0);
break;
case 1 :
c.setAttribute('width', img.height);
c.setAttribute('height', img.width);
canvasContext.rotate(90 * Math.PI / 180);
canvasContext.drawImage(img, 0, -img.height);
break;
case 2 :
c.setAttribute('width', img.width);
c.setAttribute('height', img.height);
canvasContext.rotate(180 * Math.PI / 180);
canvasContext.drawImage(img, -img.width, -img.height);
break;
case 3 :
c.setAttribute('width', img.height);
c.setAttribute('height', img.width);
canvasContext.rotate(270 * Math.PI / 180);
canvasContext.drawImage(img, -img.width, 0);
break;
}
}
}
</script>
</head>
<body>
<!--把下面代码加到<body>与</body>之间-->
<ul class="clearfix">
<li>
<div class="caption">
<input type="button" value="turn left" onclick="rotate('pic_1','left')">
<input type="button" value="turn right" onclick="rotate('pic_1','right')">
</div>
<div class="cont">
<img alt="javascript 图片旋转效果" id="pic_1" src="1.gif" alt="">
</div>
</li>
</ul>
</body>
</html>