<script language =javascript >
var curIndex=0;
  var timeInterval=2000;//时间间隔 单位毫秒
 var arr=new Array();
 arr[0]="1.bmp";
 arr[1]="2.bmp";
 
setInterval(changeImg,timeInterval);//setInterval 自动重复 setTimeout不会重复

function changeImg()
{
    var obj=document.getElementById("obj");
    if (curIndex==arr.length-1)
    {
        curIndex=0;
    }
    else
    {
        curIndex+=1;
    }
    obj.src=arr[curIndex];
}
function stop_pic()
{
   
 clearInterval(setInterval(changeImg,timeInterval));
}
</script>
<img src ="1.bmp" name="obj" border =0 id=obj />

<input type="button" onclick="stop_pic()" value="bottom">

bottom按钮不能暂停 图片切换，还请老师指教！

xxxx=setInterval(changeImg,timeInterval);
....
function stop_pic()
{
clearInterval(xxxx);
}

clearInterval 如何使用
<script language =javascript >
var curIndex=0;
  var timeInterval=2000;//时间间隔 单位毫秒
var arr=new Array();
arr[0]="1.bmp";
arr[1]="2.bmp";
var tInterval=setInterval(changeImg,timeInterval);//setInterval 自动重复 setTimeout不会重复

function changeImg()
{
    var obj=document.getElementById("obj");
    if (curIndex==arr.length-1)
    {
        curIndex=0;
    }
    else
    {
        curIndex+=1;
    }
    obj.src=arr[curIndex];
}
function stop_pic()
{
    clearInterval(tInterval);
}
</script>
<img src ="1.bmp" name="obj" border =0 id=obj />

<input type="button" onclick="stop_pic()" value="bottom">