OleDbDataAdapter.SelectCommand Proprietà

Definizione

Spazio dei nomi:
System.Data.OleDb
Assembly:
System.Data.dll

Ottiene o imposta un'istruzione SQL o una stored procedure utilizzata per selezionare i record nell'origine dati.

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

Valore della proprietà

OleDbCommand

Oggetto OleDbCommand utilizzato durante Fill(DataSet) per selezionare i record dall'origine dati per il posizionamento in DataSet.

Attributi
DataSysDescriptionAttribute

Esempio

Nell'esempio seguente viene creato un oggetto OleDbDataAdapter e vengono impostate le SelectCommand proprietà e InsertCommand . Si presuppone che sia già stato creato un OleDbConnection oggetto .

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

Commenti

Quando SelectCommand viene assegnato a un oggetto creato OleDbCommandin precedenza, l'oggetto OleDbCommand non viene clonato. SelectCommand Mantiene un riferimento all'oggetto creato OleDbCommand in precedenza.

Se restituisce SelectCommand nessuna riga, nessuna tabella viene aggiunta a DataSete non viene generata alcuna eccezione.

Si applica a

Vedi anche