Dapper(四) 高级使用_我命由我不由天_dapper 高级

1.    联合查询

A.    写法一

public user_info_model get_user_info__group_info(int id)
        {
            using (conn)
            {
                string query = @"SELECT * FROM dbo.user_info U 
                                 LEFT JOIN user_group UG 
                                 ON U.id=UG.user_info_id 
                                 WHERE U.id = @id";
                user_info_model userinfo = null;
                var b = conn.Query<user_info_model, user_group_model, user_info_model>(query,
                    (user, group) =>
                    {
                        if (userinfo == null || userinfo.id != user.id)
                            userinfo = user;
                        if (group != null)
                            userinfo.Reviews.Add(group);
                        return userinfo;
                    }, new { id },splitOn: "user_info_id").Distinct().SingleOrDefault();
                return b;
            }
        }
附:关键字Reviews在model的属性
public virtual user_group_model usergroup { get; set; }public user_info_model