上传前预览Flash也可以预览图片

 

< input type = " file "  name = " file1 "  style = " width:300' "  class = " tx1 "  value = ""  onchange = " PreviewImg(this); " >    < div style = " width:400px;height:300px;border:1px solid #aaaaaa;overflow:auto "  id = " previewDiv " >   div >< script language = " javascript " >   function  PreviewImg(obj) ... {  var div = document.getElementById("previewDiv");  if(obj.value=="" || div.childNodes.length>0)...{    div.removeChild(div.firstChild);    if(obj.value=="")return;  }  var ext = obj.value.substring(obj.value.lastIndexOf(".")+1)  div.appendChild(getFlash(obj.value,ext));} function  getFlash(src,ext) ... { var img; switch(ext.toLowerCase())...{  case "jpg":  case "jpeg":  case "bmp":  case "gif":  case "png":   img = document.createElement("img");   break;  case "swf":   img = document.createElement("embed");   img.type="application/x-shockwave-flash";   img.width=400;   img.height=300;   break; } img.src=src; return img;} script >