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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()

Return Value

Type: System.Boolean
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 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

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