取值问题

<a id="deletefileid" value='<%#Eval("FileId")%>' onclick="deletebyId()">删除</a>
今天在点击删除的时候 ID就找不到了 正在调试
var fileid = $("#deletefileid").attr("value");
 string id = context.Request["id"].ToString();
            Model.File mfile = new Model.File();
            BLL.NRBLL bnl = new BLL.NRBLL();
            Guid guidpath = new Guid(id);
            mfile.Fileid = guidpath;
            if (bnl.FN_SerchResPath(mfile) != null)
            {
                //确定这个文件的路径是否存在
                if (!Directory.Exists(bnl.FN_SerchResPath(mfile).Tables["t_file"].Rows[0]["FilePath"].ToString()))
                {
                    File.Delete(bnl.FN_SerchResPath(mfile).Tables["t_file"].Rows[0]["FilePath"].ToString());//在执行对数据库filepath的删除操作
                    Model.File mf = new Model.File();
                    BLL.NRBLL bn = new BLL.NRBLL();
                    Guid guid = new Guid(id);
                    mf.Fileid = guid;
                    //如果返回结果大于0
                    if (bn.FN_DeleteRes(mf) > 0)
                    {
                        context.Response.Write("0");
                    }
                    else
                    {
                        context.Response.Write("1");
                    }
                }
                else
                {
                    context.Response.Write("1");
                    context.Response.Close();
                }