function set_pic()
{
    iwidth=660;
    temp = document.getElementById('pic_content');
    lis = temp.getElementsByTagName('img');
    for(i=0;i<lis.length;i++)
    {

       if(lis[i].width>iwidth)
        {
            iheight=iwidth/lis[i].width*lis[i].height;
            lis[i].width=iwidth;
            lis[i].height=iheight;
            lis[i].alt="点击看大图";
            lis[i].style.cursor="hand";
            lis[i].onclick=function()
            {
                window.open(this.src);
            }
            lis[i].onmousewheel=function()
            {
                iwidth=this.width;
                
                var zoom=parseInt(this.style.zoom, 10)||100;
                zoom+=event.wheelDelta/12;
                if (zoom>100)
                {
                    iwidth=iwidth+50;
                }
                else
                {
                    iwidth=iwidth-50;
                }
                
                
                iheight=iwidth/this.width*this.height;
                this.width=iwidth;
                this.height=iheight;
                return false;
            }
        } 
    }
    

}