javascript的字節換算

function GetSizeType(size:Number) {
 if (size<1024) {
  return int(size*100)/100+" bytes";
 }
 if (size<1048576) {
  return int((size/1024)*100)/100+"KB";
 }
 if (size<1073741824) {
  return int((size/1048576)*100)/100+"MB";
 }
 return int((size/1073741824)*100)/100+"GB";
}