利用EF FromSql 自定义查询，有时间须要的字段可能是自定义的，因此须要返回自定义类的list

一、System.Data.Common

  /// <summary>
        /// EF query by sql
        /// </summary>
        /// <param name="context"></param>
        /// <param name="CommandText">select * from table where Id=@Id</param>
        /// <param name="cmdType"></param>
        /// <param name="dicParams">dicParams.Add("@Id", 1);</param>
        /// <returns></returns>
        public static DataTable GetDTableCommon(this DbContext context, string CommandText, CommandType cmdType = CommandType.Text, Dictionary<string, object> dicParams = null)
        {
            DataTable dt = new DataTable();

            DatabaseFacade dbFacade = new DatabaseFacade(context);
            var conn = dbFacade.GetDbConnection();
            conn.Open();
            DbCommand cmd = conn.CreateCommand();
            cmd.CommandText = CommandText;
            cmd.CommandType = cmdType;

            foreach (var parameter in dicParams == null ? new Dictionary<string, object>() : dicParams)
            {
                DbParameter p = cmd.CreateParameter();
                p.ParameterName = parameter.Key;
                p.Value = parameter.Value;
                cmd.Parameters.Add(p);
            }
            var dr = cmd.ExecuteReader();

            dt.Load(dr);
            dr.Close();
            conn.Close();
            return dt;
        }

二 、 FromSql

1、首先定义自定义entity 类：seller1

public partial class sellers1
{
    public int Id { get; set; }
}

2、然后在 Context类中把自定义类加入到DbSet，
PS：自动生成的Context类为Partial，为了方便管理, 可以再添加一个同样的类Context 专门来添加自定义类到Context

public partial class MyContext{
public virtual DbSet<sellers1> sellers1 { get; set; }
}

3、然后执行如下语句

var sql="select * from table"
var list1 = MyContext.Set<sellers1>().FromSql(sql).ToList();