OracleRowUpdatingEventArgs Classe

Definizione

public ref class OracleRowUpdatingEventArgs sealed : System::Data::Common::RowUpdatingEventArgs

public sealed class OracleRowUpdatingEventArgs : System.Data.Common.RowUpdatingEventArgs

type OracleRowUpdatingEventArgs = class
    inherit RowUpdatingEventArgs

Public NotInheritable Class OracleRowUpdatingEventArgs
Inherits RowUpdatingEventArgs

Ereditarietà

Object

EventArgs

RowUpdatingEventArgs

OracleRowUpdatingEventArgs

Esempio

Nell'esempio seguente viene illustrato come usare sia gli RowUpdating eventi che RowUpdated gli eventi.

L'evento RowUpdating restituisce questo output:

Event Arguments: (command=OracleCommand commandType=2 status=0)

L'evento RowUpdated restituisce questo output:

Event Arguments: (command=OracleCommand commandType=2 recordsAffected=1 row=DataRow[37] status=0)

// handler for RowUpdating event
private static void OnRowUpdating(object sender, OracleRowUpdatingEventArgs e)
{
    PrintEventArgs(e);
}

//Handler for RowUpdated event.
private static void OnRowUpdated(object sender, OracleRowUpdatedEventArgs e)
{
    PrintEventArgs(e);
}

public static int Main(String[] args)
{
    const string CONNECTION_STRING = "Data Source=Oracle8i;Integrated Security=yes";
    const string SELECT_ALL = "SELECT * FROM Scott.Emp";

    //Create DataAdapter.
    OracleDataAdapter rAdapter    = new OracleDataAdapter(SELECT_ALL, CONNECTION_STRING);

    //Create and fill DataSet (Select only first 5 rows.).
    DataSet rDataSet = new DataSet();
    rAdapter.Fill(rDataSet, 0, 5, "Table");

    //Modify DataSet.
    DataTable rTable = rDataSet.Tables["Table"];
    rTable.Rows[0][1] = "DYZY";

    //Add handlers.
    rAdapter.RowUpdating += new OracleRowUpdatingEventHandler( OnRowUpdating );
    rAdapter.RowUpdated += new OracleRowUpdatedEventHandler( OnRowUpdated );

    //Update--this operation fires two events (RowUpdating and RowUpdated) for each changed row.
    rAdapter.Update(rDataSet, "Table");

    //Remove handlers.
    rAdapter.RowUpdating -= new OracleRowUpdatingEventHandler( OnRowUpdating );
    rAdapter.RowUpdated -= new OracleRowUpdatedEventHandler( OnRowUpdated );
    return 0;
}

private static void PrintEventArgs(OracleRowUpdatingEventArgs args)
{
    Console.WriteLine("OnRowUpdating");
    Console.WriteLine("  event args: ("+
        " command=" + args.Command +
        " commandType=" + args.StatementType +
        " status=" + args.Status + ")");
}

private static void PrintEventArgs(OracleRowUpdatedEventArgs args)
{
    Console.WriteLine("OnRowUpdated");
    Console.WriteLine("  event args: ("+
        " command=" + args.Command +
        " commandType=" + args.StatementType +
        " recordsAffected=" + args.RecordsAffected +
        " status=" + args.Status + ")");
}

'Handler for RowUpdating event.
Private Shared Sub OnRowUpdating(sender As Object, e As OracleRowUpdatingEventArgs)
    PrintEventArgs(e)
End Sub

'Handler for RowUpdated event.
Private Shared Sub OnRowUpdated(sender As Object, e As OracleRowUpdatedEventArgs)
    PrintEventArgs(e)
End Sub

'Entry point which delegates to C-style main Private Function.
Public Overloads Shared Sub Main()
    System.Environment.ExitCode = Main(System.Environment.GetCommandLineArgs())
End Sub

Overloads Public Shared Function Main(args() As String) As Integer
    Const CONNECTION_STRING As String = "Data Source=Oracle8i;Integrated Security=yes"
    Const SELECT_ALL As String = "SELECT * FROM Scott.Emp"
    
    'Create DataAdapter.
    Dim rAdapter As New OracleDataAdapter(SELECT_ALL, CONNECTION_STRING)
    
    'Create and fill DataSet (Select only first 5 rows.).
    Dim rDataSet As New DataSet()
    rAdapter.Fill(rDataSet, 0, 5, "Table")
    
    'Modify DataSet.
    Dim rTable As DataTable = rDataSet.Tables("Table")
    rTable.Rows(0)(1) = "DYZY"
    
    'Add handlers.
    AddHandler rAdapter.RowUpdating, AddressOf OnRowUpdating
    AddHandler rAdapter.RowUpdated, AddressOf OnRowUpdated
    
    'Update--this operation fires two events (RowUpdating and RowUpdated) for each changed row. 
    rAdapter.Update(rDataSet, "Table")
    
    'Remove handlers.
    RemoveHandler rAdapter.RowUpdating, AddressOf OnRowUpdating
    RemoveHandler rAdapter.RowUpdated, AddressOf OnRowUpdated
    Return 0
End Function 'Main

Overloads Private Shared Sub PrintEventArgs(args As OracleRowUpdatingEventArgs)
    Console.WriteLine("OnRowUpdating")
    Console.WriteLine("  event args: (" & _
                    " command=" & _
                    args.Command.CommandText & _
                    " commandType=" & _
                    args.StatementType & _
                    " status=" & _
                    args.Status & _
                    ")")
End Sub


Overloads Private Shared Sub PrintEventArgs(args As OracleRowUpdatedEventArgs)
    Console.WriteLine("OnRowUpdated")
    Console.WriteLine("  event args: (" & _
                    " command=" & _
                    args.Command.CommandText & _
                    " commandType=" & _
                    args.StatementType & _
                    " recordsAffected=" & _
                    args.RecordsAffected & _
                    " status=" & _
                    args.Status & _
                    ")")
End Sub

Commenti

L'evento RowUpdating viene generato prima Update di una riga.

Quando si usa Update, sono presenti due eventi che si verificano per ogni riga di dati aggiornata. L'ordine di esecuzione è il seguente:

1. I valori nell'oggetto DataRow vengono spostati nei valori dei parametri.

2. Viene generato l'evento OnRowUpdating.

3. Il comando viene eseguito.

4. Se il comando è impostato su FirstReturnedRecord, il primo risultato restituito viene inserito in DataRow.

5. Se sono presenti parametri di output, vengono inseriti in DataRow.

6. Viene generato l'evento OnRowUpdated.

7. Chiamata del metodo AcceptChanges.

Costruttori

Proprietà

Metodi

Si applica a