java 实现图片90.180.270.360°旋转

/*旋转图片******************************************
* p 选择旋转方向,固定值为'left'或'right';
*/
function rotate(p){
 var img = document.getElementById('zoomimg');
 var zoomimglayer=document.getElementById('zoomimglayer');
 document.getElementById('zoomimgbox').style.textAlign='left';
 if(!img || !p) return false;
 var n = img.getAttribute('step');
 if(n== null) n=0;
 if(p=='left'){
  (n==3)? n=0:n++;
 }else if(p=='right'){
  (n==0)? n=3:n--;
 }
 img.setAttribute('step',n);
 //alert(n)
 //IE 

 if(document.all) {
  img.style.filter = 'progid:DXImageTransform.Microsoft.BasicImage(rotation='+ n +')';
  //HACK FOR MSIE 8
  switch(n){
   case 0:
    img.parentNode.style.height = img.height;
    zoomimglayer.style.width=(img.width+20)+"px";
    img.parentNode.style.width=img.width;
    break;