OracleDataReader.Read Metod

public:
 virtual bool Read();

public:
 override bool Read();

public bool Read();

public override bool Read();

abstract member Read : unit -> bool
override this.Read : unit -> bool

override this.Read : unit -> bool

Public Function Read () As Boolean

Public Overrides Function Read () As Boolean

Returer

trueom det finns fler rader; annars . false

Implementeringar

Exempel

I följande exempel skapas en OracleConnection, en OracleCommandoch en OracleDataReader. Exemplet läser igenom data och skriver ut dem till konsolen. Slutligen stänger OracleDataReaderexemplet , och sedan OracleConnection.

private static void ReadData(string connectionString)
{
    string queryString = "SELECT OrderID, CustomerID FROM Orders";
    using (OracleConnection connection = new OracleConnection(connectionString))
    {
        OracleCommand command = new OracleCommand(queryString, connection);
        connection.Open();
        OracleDataReader reader;
        reader = command.ExecuteReader();

        // Always call Read before accessing data.
        while (reader.Read())
        {
            Console.WriteLine(reader.GetInt32(0) + ", " + reader.GetString(1));
        }

        // Always call Close when done reading.
        reader.Close();
    }
}

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

Kommentarer

Standardpositionen för OracleDataReader är före den första posten. Därför måste du anropa Read för att börja komma åt data.

Fler än en OracleDataReader kan vara öppen vid en viss tidpunkt.