$('#file_upload').uploadify({ 
buttonImage: '${ctx }/commons/uploaddify/img/browse-btn.png', 
swf :'${ctx }/commons/uploaddify/uploadify.swf', 
uploader :'../servlet/defaultDispatcher;jsessionid=${pageContext.session.id}?__action=xxx', 
fileTypeExts: '*.jpg;*.png;*.gif;*.bmp', 
fileTypeDesc: '图像文件', 
formData: { 
timestamp: new Date().getTime() 
}, 
onSelect: function(file){ 
//重写校验 
}, 
onUploadProgress: function(file,bytesUploaded,bytesTotal,totalBytesUploaded,totalBytesTotal){ 
$('#pregress').html('总共需要上传'+bytesTotal+'字节，'+'已上传'+totalBytesTotal+'字节'); 
}, 
onUploadSuccess: function(file){ 
//上传成功 
} 
});