System.InvalidCastException：指定的强制转换无效

Question

I retrieve a table from the database that contains a column of type "time" in sql server, and I try to assign this to a DateTime variable but i get this error: System.InvalidCastException: Specified cast is not valid.

here's my c# code:

DateTime StartTime = (DateTime)dt.Rows[i]["startTime"];

knowing that the column "startTime" is of type "time" and I can change it in the database. any help??

Answer 1

DateTime StartTime = Convert.ToDateTime(dt.Rows[i]["startTime"].ToString());

如果你知道它可能是null ..

DateTime StartTime = (dt.Rows[i]["startTime"] == DBNull.Value ? DateTime.MinValue : Convert.ToDateTime(dt.Rows[i]["startTime"].ToString()));

Answer 2

您应该能够将其转换为TimeSpan ：

var startTime = dt.Rows<TimeSpan>("startTime");