如何将预先下载的图片用于改变背景图片？

Question

<script>
var imga = new Array("http://dotnet.aspx.cc/Images/banner.gif","http://dotnet.aspx.cc/Images/logoSite.gif");
var imgb = new Array()
for(var i=0; i<imga.length; i++)
{
  imgb[i] = new Image();
  imgb[i].src = imga[i];
}</script>
<input onclick="this.style.backgroundImage='url('+imgb[0].src+')'; " style="width:600px;height:299px;background-image:url()">
<input onclick="this.style.backgroundImage='url('+imgb[1].src+')'; " style="width:600px;height:299px;background-image:url()">

Answer 1

this.style.backgroundImage='url('+images[0].src+')';

Answer 2

imgb[i] = new Image();
  imgb[i].src = imga[i];
就可以