js上传图片及时显示

 $("#upfile").change(function(){
      var objUrl=getURL(this.files[0]);
      if(objUrl){
      $("img").attr("src",objUrl); 
   }
 })


 9       function getUrl(file){
            var url=null;
            if (window.createObjectURL != undefined) { 
                url = window.createObjectURL(file);
            } else if (window.URL != undefined) { 
                url = window.URL.createObjectURL(file);
            } else if (window.webkitURL != undefined) { 
                url = window.webkitURL.createObjectURL(file);
            }
            return url;
      }