Assembly: System.Data (in system.data.dll)
While the OleDbDataReader is being used, the associated OleDbConnection is busy serving the OleDbDataReader, and no other operations can be performed on the OleDbConnection other than closing it. This is the case until the Close method of the OleDbDataReader is called. For example, you cannot retrieve output parameters until after you call Close.
Changes made to a result set by another process or thread while data is being read may be visible to the user of the OleDbDataReader. However, the precise behavior is timing dependent.
IsClosed and RecordsAffected are the only properties that you can call after the OleDbDataReader is closed. Although the RecordsAffected property may be accessed while the OleDbDataReader exists, always call Close before returning the value of RecordsAffected to guarantee an accurate return value.
The following example creates an OleDbConnection, an OleDbCommand, and an OleDbDataReader. The example reads through the data, writing it out to the console. Finally, the example closes the OleDbDataReader and then the OleDbConnection.
Public Sub ReadData(ByVal connectionString As String, _ ByVal queryString As String) Using connection As New OleDbConnection(connectionString) Dim command As New OleDbCommand(queryString, connection) connection.Open() Dim reader As OleDbDataReader = command.ExecuteReader() While reader.Read() Console.WriteLine(reader(0).ToString()) End While reader.Close() End Using End Sub
Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter EditionThe Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.