How do I convert a DateTime table column to a TimeSpan or DayOfWeek ?

The context is shown below in the getGames() method.

I get errors on these lines:

dtGames.Rows[i]["playTime"] = (TimeSpan)dtGames.Rows[i]["playDate"];
dtGames.Rows[i]["playDay"] = (DayOfWeek)dtGames.Rows[i]["playDate"];

because the playDate column is a DateTime.

Here is my solution but I don't like it. What else can I do?

dtGames.Rows[i]["playTime"] =
Convert.ToDateTime(dtGames.Rows[i]["playDate"]).TimeOfDay;
dtGames.Rows[i]["playDay"] =
Convert.ToDateTime(dtGames.Rows[i]["playDate"]).DayOfWeek;


public DataView getGames()
{
DataTable dtGames = DAL.GetTable("Games");
DataColumn colItem;

colItem = new DataColumn("playTime",
Type.GetType("System.TimeSpan"));
dtGames.Columns.Add(colItem);

colItem = new DataColumn("playDay",
Type.GetType("System.DayOfWeek"));
dtGames.Columns.Add(colItem);

for (int i = 0; i <= dtGames.Rows.Count - 1; i++)
{
dtGames.Rows[i]["playTime"] =
(TimeSpan)dtGames.Rows[i]["playDate"];
dtGames.Rows[i]["playDay"] =
(DayOfWeek)dtGames.Rows[i]["playDate"];
}

dvwGames = dtGames.DefaultView;
Cache.Insert("Games", dvwGames);
return dvwGames;
}

Harry Haller