JavaScript就这么回事3：图像
36 读取图像属性
<img src="/”image1.jpg"” name=”myImage”>
<a href=”# ” onClick=”window.alert(document.myImage.width)”>Width</a>
37 动态加载图像
<script language=”JavaScript”>
myImage = new Image;
myImage.src = “Tellers1.jpg”;
</script>
38 简单的图像替换
<script language=”JavaScript”>
rollImage = new Image;
rollImage.src = “rollImage1.jpg”;
defaultImage = new Image;
defaultImage.src = “image1.jpg”;
</script>
<a href="/”myUrl"” onMouseOver=”document.myImage.src = rollImage.src;”
onMouseOut=”document.myImage.src = defaultImage.src;”>
<img src="/”image1.jpg"” name=”myImage” width=100 height=100 border=0>
39 随机显示图像
<script language=”JavaScript”>
var imageList = new Array;
imageList[0] = “image1.jpg”;
imageList[1] = “image2.jpg”;
imageList[2] = “image3.jpg”;
imageList[3] = “image4.jpg”;
var imageChoice = Math.floor(Math.random() * imageList.length);
document.write(‘<img src=”’ + imageList[imageChoice] + ‘“>’);
</script>
40 函数实现的图像替换
<script language=”JavaScript”>
var source = 0;
var replacement = 1;
function createRollOver(originalImage,replacementImage) {
var imageArray = new Array;
imageArray[source] = new Image;
imageArray[source].src = originalImage;
imageArray[replacement] = new Image;
imageArray[replacement].src = replacementImage;
return imageArray;
}
1 var rollImage1 = createRollOver(“image1.jpg”,”rollImage1.jpg”);
1</script>
1<a href=”#” onMouseOver=”document.myImage1.src = rollImage1[replacement].src;”
1onMouseOut=”document.myImage1.src = rollImage1[source].src;”>
1 <img src="/”image1.jpg"” width=100 name=”myImage1” border=0>
1 </a>
41 创建幻灯片
<script language=”JavaScript”>
var imageList = new Array;
imageList[0] = new Image;
imageList[0].src = “image1.jpg”;
imageList[1] = new Image;
imageList[1].src = “image2.jpg”;
imageList[2] = new Image;
imageList[2].src = “image3.jpg”;
imageList[3] = new Image;
imageList[3].src = “image4.jpg”;
function slideShow(imageNumber) {
1 document.slideShow.src = imageList[imageNumber].src;
1imageNumber += 1;
1if (imageNumber < imageList.length) {
1window.setTimeout(“slideShow(“ + imageNumber + “)”,3000);
1 }
1 }
1 </script>
1 </head>
20: <body onLoad=”slideShow(0)”>
21: <img src="/”image1.jpg"” width=100 name=”slideShow”>
42 随机广告图片
<script language=”JavaScript”>
var imageList = new Array;
imageList[0] = “image1.jpg”;
imageList[1] = “image2.jpg”;
imageList[2] = “image3.jpg”;
imageList[3] = “image4.jpg”;
var urlList = new Array;
urlList[0] = “http://some.host/”;
urlList[1] = “http://another.host/”;
urlList[2] = “http://somewhere.else/”;
urlList[3] = “http://right.here/”;
1 var imageChoice = Math.floor(Math.random() * imageList.length);
1document.write(‘<a href=”’ + urlList[imageChoice] + ‘“><img src=”’ + imageList[imageChoice] + ‘“></a>’);
1</script>
