我有一个两步表单流程，其中第一组数据存储在session中。[IsMp4File][Required(ErrorMessage="*Pleaseselectavideotoupload")]publicHttpPostedFileBaseVideoClip{get;set;}[Required(ErrorMessage="*Pleaseselectathumbmailimage")]publicHttpPostedFileBaseVideoThumbnail{get;set;}publicstringVideoFileName{get{returnVideoClip.FileName;