将 DataTable 转换为 IEnumerable<T>; [英] Convert DataTable to IEnumerable&lt;T&gt;

问题描述

我正在尝试将 DataTable 转换为 IEnumerable.其中 T 是我创建的自定义类型.我知道我可以通过创建一个 List 来做到这一点，但我在想是否有使用 IEnumerable 的更灵活的方法来做到这一点.这是我现在所拥有的:

I am trying to convert a DataTable to an IEnumerable. Where T is a custom type I created. I know I can do it by creating a List<T> but I was thinking if there is a slicker way to do it using IEnumerable. Here is what I have now:

private IEnumerable<TankReading> ConvertToTankReadings(DataTable dataTable)
{
    var tankReadings = new List<TankReading>();
    foreach (DataRow row in dataTable.Rows)
    {
        var tankReading = 
              new TankReading
              {
                  TankReadingsID = Convert.ToInt32(row["TRReadingsID"]),
                  TankID = Convert.ToInt32(row["TankID"]),
                  ReadingDateTime = Convert.ToDateTime(row["ReadingDateTime"]),
                  ReadingFeet = Convert.ToInt32(row["ReadingFeet"]),
                  ReadingInches = Convert.ToInt32(row["ReadingInches"]),
                  MaterialNumber = row["MaterialNumber"].ToString(),
                  EnteredBy = row["EnteredBy"].ToString(),
                  ReadingPounds = Convert.ToDecimal(row["ReadingPounds"]),
                  MaterialID = Convert.ToInt32(row["MaterialID"]),
                  Submitted = Convert.ToBoolean(row["Submitted"]),
              };

        tankReadings.Add(tankReading);
    }
    return tankReadings.AsEnumerable();
}

关键部分是我正在创建一个 List 然后使用 AsEnumerable() 返回它.

The key part being I am creating a List<T> then returning it using AsEnumerable().

推荐答案

该实现没有任何问题.你可以试试 yield 关键字，看看你喜欢它:

Nothing wrong with that implementation. You might give the yield keyword a shot, see how you like it:

private IEnumerable<TankReading> ConvertToTankReadings(DataTable dataTable)
    {
        foreach (DataRow row in dataTable.Rows)
        {
            yield return new TankReading
                                  {
                                      TankReadingsID = Convert.ToInt32(row["TRReadingsID"]),
                                      TankID = Convert.ToInt32(row["TankID"]),
                                      ReadingDateTime = Convert.ToDateTime(row["ReadingDateTime"]),
                                      ReadingFeet = Convert.ToInt32(row["ReadingFeet"]),
                                      ReadingInches = Convert.ToInt32(row["ReadingInches"]),
                                      MaterialNumber = row["MaterialNumber"].ToString(),
                                      EnteredBy = row["EnteredBy"].ToString(),
                                      ReadingPounds = Convert.ToDecimal(row["ReadingPounds"]),
                                      MaterialID = Convert.ToInt32(row["MaterialID"]),
                                      Submitted = Convert.ToBoolean(row["Submitted"]),
                                  };
        }

    }

还有 AsEnumerable 不是必需的，因为 List 已经是 IEnumerable

Also the AsEnumerable isn't necessary, as List<T> is already an IEnumerable<T>

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