网页特效---下拉列表直接选择背景

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<title>网页特效---下拉列表直接选择背景</title>
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A {
	COLOR: black; FONT-SIZE: 9pt; FONT-WEIGHT: 400; TEXT-DECORATION: none
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	COLOR: #ff0033; CURSOR: hand; FONT: 9pt "宋体"
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<meta content="text/html; charset=gb2312" http-equiv="Content-Type">
<script language="JavaScript">

<!--

image1= new Image();

image1.src = "images/SHU.JPG";

image2= new Image();

image2.src = "images/A.GIF";

image3= new Image();

image3.src = "images/B.jpg";
image4= new Image();

image4.src = "images/C.jpg";

function imgchange(){

var imageNum =  document.form.selImage.selectedIndex + 1;

fname = eval("image" + imageNum + ".src")

document.body.background =  eval("image" + imageNum + ".src")
//eval(imgName + ".src");
}

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<p align="center"><font face="隶书" size="5" color="#0000FF"><strong>下拉列表直接选择背景</strong></font></p>

<table border="1" borderColor="#0000FF" borderlight="green" height="150" width="410" bordercolorlight="#00FFFF" bordercolordark="#0000FF" style="border-collapse: collapse" cellpadding="0" cellspacing="0">
<TBODY>
  <tr>
    <td align="middle" height="24" width="404"><strong><font color="red" size="5">  </font><font  
    face="宋体" size="3" color="#0000FF">一般网页的背景图片都是设计时设置的,在浏览时不能改动,这里提供一个可以浏览时通过下拉列表动态改变背景的特效,在下面由列表选择图片项目后,再单击“显示”按钮,可以使窗口动态改变背景，使网页更有交互性。</font></strong></td>  
  </tr>  
  <tr>  
    <td align="center" height="114" width="404"><form name="form">  
      <p align="center"><select name="selImage" size="1">  
        <option selected value="欢迎光临 请选择背景">欢迎光临 请选择背景</option>  
        <option value="蓝天白云">蓝天白云</option>  
        <option value="鹅卵石">鹅卵石</option>  
        <option value="石块">石块</option>  
      </select><input onclick="imgchange()" type="button" value="显示"> </p>  
    </form>  
    <p>　</td>  
  </tr>  
</TBODY>  
</table>  
</center></div>  
  
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