singleordefault(where) 条件不支持动态

所以想要达到目标，就需要转换思路，把where在前面调用，然后再接，代码如下

        public TResult GetSingle<T, TResult>(Expression<Func<T, bool>> exWhere, Expression<Func<T, TResult>> selector) where T : class
        {
            using (SysDb<T> db = new SysDb<T>(strConn))
            {
                return db.Set<T>().AsExpandable().Where(exWhere).Select(selector).SingleOrDefault();
            }
        }

使用：

            dynamic v_sysuser = basebll_Jyxt.GetSingle<V_SysUserAndBC, dynamic>
                (c => (c.UserCode == hdnUserCode && c.IsQYUser == true), 
                c => new { c.SubSystemName });