OleDbDataReader.Read Metode

Definisi

Ruang nama:

System.Data.OleDb

Rakitan:

System.Data.OleDb.dll

Paket:

System.Data.OleDb v9.0.0-preview.4.24266.19

Sumber:

OleDbDataReader.cs

Memajukan OleDbDataReader ke rekaman berikutnya.

public:
 override bool Read();

public override bool Read ();

override this.Read : unit -> bool

Public Overrides Function Read () As Boolean

Mengembalikan

Boolean

true jika ada lebih banyak baris; jika tidak, false.

Contoh

Contoh berikut membuat OleDbConnection, , OleDbCommanddan OleDbDataReader. Contohnya membaca data, menulisnya ke konsol. Akhirnya, contoh menutup OleDbDataReader dan kemudian OleDbConnection.

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

Keterangan

Posisi OleDbDataReader default adalah sebelum rekaman pertama. Oleh karena itu, Anda harus memanggil Read untuk mulai mengakses data apa pun.

OleDbDataReader Saat sedang digunakan, yang terkait OleDbConnection sibuk melayaninya sampai Anda memanggil Close.

Lihat juga

• DataAdapters dan DataReaders