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IDataReader.Read Method

Advances the IDataReader to the next record.

Namespace: System.Data
Assembly: System.Data (in system.data.dll)

'Declaration
Function Read As Boolean
'Usage
Dim instance As IDataReader
Dim returnValue As Boolean

returnValue = instance.Read
boolean Read ()
function Read () : boolean
Not applicable.

Return Value

true if there are more rows; otherwise, false.

The default position of the IDataReader is prior to the first record. Therefore you must call Read to begin accessing any data.

While the data reader is in use, the associated connection is busy serving the IDataReader. This is the case until Close is called.

The following example creates instances of three derived classes OleDbConnection, an OleDbCommand, and an OleDbDataReader. The example reads through the data, writing it out to the console. Finally, the example closes the OleDbDataReader, then the OleDbConnection.

Public Sub ReadData(ByVal connectionString As String)
    Dim queryString As String = _
        "SELECT OrderID, CustomerID FROM Orders"

    Using connection As New OracleConnection(connectionString)
        Dim command As New OracleCommand(queryString, connection)
        connection.Open()

        Dim reader As OracleDataReader
        reader = command.ExecuteReader()

        ' Always call Read before accessing data.
        While reader.Read()
            Console.WriteLine(reader.GetInt32(0) & ", " & reader.GetString(1))
        End While

        ' Always call Close when done reading.
        reader.Close()
    End Using
End Sub

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

XNA Framework

Supported in: 1.0
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