JavaScript就这么回事3：图像

luckfly

36 读取图像属性

img src=”image1.jpg” name=”myImage”>

a href=”# ” onClick=”window.alert(document.myImage.width)”>Width

37 动态加载图像

script language=”JavaScript”>

myImage = new Image;

myImage.src = “Tellers1.jpg”;

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”;
  

  

  

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] + ‘“>’);
  

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;

}

var rollImage1 = createRollOver(“image1.jpg”,”rollImage1.jpg”);

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) {

document.slideShow.src = imageList[imageNumber].src;

imageNumber += 1;

if (imageNumber imageList.length) {

window.setTimeout(“slideShow(“ + imageNumber + “)”,3000);

}

}

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/”;

var imageChoice = Math.floor(Math.random() * imageList.length);

document.write(‘a href=”’ + urlList[imageChoice] + ‘“>img src=”’ + imageList[imageChoice] + ‘“>a>’);

本文来自ChinaUnix博客，如果查看原文请点：http://blog.chinaunix.net/u/15511/showart_97519.html