迭代值 [英] Iterating values

问题描述

我是linq的新手.我正在使用linq从数据库中填充一些类.

I'm new to linq. I'm using linq to fill some classes from the database.

我的所有对象都使用linq正确填充，除了一件小东西.在下面，您可以看到"SAR"飞行方向"(行15,16)的值应为升序和降序.但是我得到的是升序"的两个值对象.

All my objects are being filled correctly using my linq except for one small thing. Below you can see that for "SAR" "Flight Direction" (rows 15,16) I should have a value for Ascending and a value for Descending. But what I'm getting are two value objects for "Ascending".

为什么它没有遍历我的价值观? LINQ缺少什么?

using (NpgsqlDataReader reader = command.ExecuteReader())
{

    if (reader.HasRows)
    {

        var groups = reader.Cast<System.Data.Common.DbDataRecord>()
            .GroupBy(dr => new { ID = (int)dr["id"], AttID = (int)dr["AttId"] })
            .GroupBy(g => g.Key.ID);

        typeDataList = (
            from typeGroup in groups
            let typeRow = typeGroup.First().First()
            select new TypeData()
            {
                ID = (int) typeRow["id"],
                Type = (string) typeRow["type"],
                Attributes = 
                (
                    from attGroup in typeGroup
                    let attRow = attGroup.First()
                    select new TypeDataAttribute()
                    {
                        ID = (int)attRow["AttId"],
                        Label = (string)attRow["label"],
                        PossibleValues =
                        (
                            from row in attGroup
                            where !DBNull.Value.Equals(attRow["AttValueId"])
                            select new TypeDataAttributeValue() { ID = (int)attRow["AttValueId"], Value = (string)attRow["value"] }
                        ).ToArray()
                    }
                ).ToArray()
            }
        );
    }
}

推荐答案

您要从attRow中获取Value，您应该从row中获取它.

You are taking Value from attRow, you should take it from row.

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