OleDbDataAdapter.SelectCommand Propriedade

Definição

Obtém ou define uma instrução SQL ou um procedimento armazenado usado para selecionar registros na fonte de dados.Gets or sets an SQL statement or stored procedure used to select records in the data source.

public:
 property System::Data::OleDb::OleDbCommand ^ SelectCommand { System::Data::OleDb::OleDbCommand ^ get(); void set(System::Data::OleDb::OleDbCommand ^ value); };
[System.Data.DataSysDescription("DbDataAdapter_SelectCommand")]
public System.Data.OleDb.OleDbCommand SelectCommand { get; set; }
member this.SelectCommand : System.Data.OleDb.OleDbCommand with get, set
Public Property SelectCommand As OleDbCommand

Valor da propriedade

Um OleDbCommand que é usado durante o Fill(DataSet) para selecionar registros da fonte de dados para o posicionamento no DataSet.An OleDbCommand that is used during Fill(DataSet) to select records from data source for placement in the DataSet.

Atributos

Exemplos

O exemplo a seguir cria OleDbDataAdapter um e define SelectCommand as InsertCommand Propriedades e.The following example creates an OleDbDataAdapter and sets the SelectCommand and InsertCommand properties. Ele pressupõe que você já criou um OleDbConnection objeto.It assumes that you have already created an OleDbConnection object.

public static OleDbDataAdapter CreateCustomerAdapter(
    OleDbConnection connection)
{
    OleDbDataAdapter adapter = new OleDbDataAdapter();
    OleDbCommand command;

    // Create the SelectCommand.
    command = new OleDbCommand("SELECT * FROM Customers " +
        "WHERE Country = ? AND City = ?", connection);

    command.Parameters.Add("Country", OleDbType.VarChar, 15);
    command.Parameters.Add("City", OleDbType.VarChar, 15);

    adapter.SelectCommand = command;

    // Create the InsertCommand.
    command = new OleDbCommand(
        "INSERT INTO Customers (CustomerID, CompanyName) " +
        "VALUES (?, ?)", connection);

    command.Parameters.Add(
        "CustomerID", OleDbType.Char, 5, "CustomerID");
    command.Parameters.Add(
        "CompanyName", OleDbType.VarChar, 40, "CompanyName");

    adapter.InsertCommand = command;
    return adapter;
}
Public Shared Function CreateCustomerAdapter( _
    connection As OleDbConnection) As OleDbDataAdapter 

    Dim adapter As New OleDbDataAdapter()
    Dim command As OleDbCommand

    ' Create the SelectCommand.
    command = New OleDbCommand("SELECT * FROM Customers " & _
        "WHERE Country = ? AND City = ?", connection)

    command.Parameters.Add("Country", OleDbType.VarChar, 15)
    command.Parameters.Add("City", OleDbType.VarChar, 15)

    adapter.SelectCommand = command

    ' Create the InsertCommand.
    command = New OleDbCommand( _
        "INSERT INTO Customers (CustomerID, CompanyName) " & _
        "VALUES (?, ?)", connection)

    command.Parameters.Add( _
        "CustomerID", OleDbType.Char, 5, "CustomerID")
    command.Parameters.Add( _
        "CompanyName", OleDbType.VarChar, 40, "CompanyName")

    adapter.InsertCommand = command
    Return adapter
End Function

Comentários

Quando SelectCommand é atribuído a um criado OleDbCommandanteriormente, o OleDbCommand não é clonado.When SelectCommand is assigned to a previously created OleDbCommand, the OleDbCommand is not cloned. O SelectCommand mantém uma referência ao objeto criado OleDbCommand anteriormente.The SelectCommand maintains a reference to the previously created OleDbCommand object.

Se o SelectCommand não retornar nenhuma linha, nenhuma tabela será adicionada DataSetao, e nenhuma exceção será gerada.If the SelectCommand returns no rows, no tables are added to the DataSet, and no exception is raised.

Aplica-se a

Veja também