把.netcore 2.2升级到3.1后，EFcore里，执行自己写的sql一直报错。部分代码如下：

//using System.Data.SqlClient;
  List<SmallOrderResp> result = new List<SmallOrderResp>();
            string sql = @"select * from cs_orders";
            SqlParameter[] parameters = {
                           new SqlParameter("@app_user_id",app_user_id)
                   };
            result= this.QueryBySql<SmallOrderResp>(sql, parameters).ToList();

　　

 /// <summary>
        /// 执行SQL查询-返回List
        /// </summary>
        public virtual IEnumerable<Entity> QueryBySql<Entity>(string sql, object[] parameters = null)
        {
            DbConnection connection = _dbContext.Database.GetDbConnection();
            DbCommand cmd = connection.CreateCommand();
            connection.Open();
            cmd.CommandText = sql;
            cmd.CommandType = CommandType.Text;
            if (parameters != null)
            {
                cmd.Parameters.AddRange(parameters);
            }
            DataTable dt = new DataTable();
            using (DbDataReader reader = cmd.ExecuteReader())
            {
                dt.Load(reader);
                cmd.Parameters.Clear();
            }
            connection.Close();
            return ConvertHelper.DataTableToIList<Entity>(dt).ToList();
        }

　　

简单的错误信息如下：

The SqlParameterCollection only accepts non-null SqlParameter type objects, not SqlParameter objects.

　　详细信息如下：

   at Microsoft.Data.SqlClient.SqlParameterCollection.ValidateType(Object value)
   at Microsoft.Data.SqlClient.SqlParameterCollection.AddRange(Array values)
   at MuXue.Zyiz.Template.Infrastructure.Repository.BaseRepository`1.QueryBySql[Entity](String sql, Object[] parameters) in D:\VSWrok\MuXue.Zyiz.Template.WebApi\MuXue.Zyiz.Template.Infrastructure\Repository\BaseRepository.cs:line 609
   at MuXue.Zyiz.Template.Infrastructure.Repository.ordersRepository.<QueryListSmallModel>d__1.MoveNext() in D:\VSWrok\MuXue.Zyiz.Template.WebApi\MuXue.Zyiz.Template.Infrastructure\Repository\ordersRepository.cs:line 38
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at MuXue.Zyiz.Template.Service.Impl.ordersService.<GetList>d__9.MoveNext() in D:\VSWrok\MuXue.Zyiz.Template.WebApi\MuXue.Zyiz.Template.Service\Impl\ordersService.cs:line 63

　　找了很长时间一直未找到解决方案，最终在github上找到问题所在：

https://github.com/dotnet/efcore/issues/16812

原来是 

using System.Data.SqlClient;

　　这个的错误，.netcore 3.1以后，就不能用这个了。需要用另一个，如下。

Microsoft.Data.SqlClient