/// <summary>
/// Returns a column in datareader to specified type
/// Use Nullable(Of ) for columns that can be DbNull
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="reader"></param>
/// <param name="columnName"></param>
/// <returns></returns>
/// <remarks></remarks>
public static T GetItemAs <T>(this System.Data.IDataReader reader, string columnName)
{
if (reader.IsDBNull(reader.GetOrdinal(columnName)))
{
if (typeof(T).IsGenericType && typeof(T).GetGenericTypeDefinition() == typeof(Nullable <>))
{
return(reader.GetItemAsNullable <T>(columnName));
}
if (typeof(T) == typeof(string))
{
return(default(T));
}
throw new InvalidCastException(string.Format("Column {0} is DbNull, use a Nullable(Of {1}) type", columnName, typeof(T)));
}
return((T)reader[columnName]);
}