html code如何做到random出圖的效果

你把以下html code 放到你想圖顯示的地方
img_list 裝住可供選擇的圖的path
由於Yahoo的顯示限制, 請自行刪取不必要的空格.

< img id =" my_img " src = " " />
< script language = " javascript " >
var img_list = [ " num1.png ", " num2.png " ];
random_image( " my_img " , img_list);
function random_image(tag_name, img_list)
{
var index = Math.floor(Math.random() * img_list.length);
var my_img = document.getElementById(tag_name);
if (my_img)
my_img.src = img_list[index];
}
< /script>