OleDbDataAdapter.RowUpdated Událost

Definice

Vyvolá Update(DataSet) se v průběhu po provedení příkazu proti zdroji dat.Occurs during Update(DataSet) after a command is executed against the data source. Byl proveden pokus o aktualizaci.The attempt to update is made. Proto dojde k události.Therefore, the event occurs.

public:
 event System::Data::OleDb::OleDbRowUpdatedEventHandler ^ RowUpdated;
public event System.Data.OleDb.OleDbRowUpdatedEventHandler RowUpdated;
public event System.Data.OleDb.OleDbRowUpdatedEventHandler? RowUpdated;
[System.Data.DataSysDescription("DbDataAdapter_RowUpdated")]
public event System.Data.OleDb.OleDbRowUpdatedEventHandler RowUpdated;
member this.RowUpdated : System.Data.OleDb.OleDbRowUpdatedEventHandler 
[<System.Data.DataSysDescription("DbDataAdapter_RowUpdated")>]
member this.RowUpdated : System.Data.OleDb.OleDbRowUpdatedEventHandler 
Public Custom Event RowUpdated As OleDbRowUpdatedEventHandler 

Event Type

OleDbRowUpdatedEventHandler
Atributy

Příklady

Následující příklad ukazuje RowUpdating události a, které RowUpdated jsou používány.The following example shows the RowUpdating and RowUpdated events being used.

public static void CreateDataAdapter(
    string connectionString)
{
    using (OleDbConnection connection = new OleDbConnection(connectionString))
    {
        OleDbDataAdapter adapter = new OleDbDataAdapter(
            "SELECT * FROM Customers WHERE CustomerID = 'ALFKI'", connection);

        adapter.InsertCommand = new OleDbCommand(
            "INSERT INTO Customers (CustomerID, CompanyName) VALUES(?, ?)",
            connection);

        adapter.InsertCommand.Parameters.Add(
            "@CustomerID", OleDbType.VarChar, 5, "CustomerID");
        adapter.InsertCommand.Parameters.Add(
            "@CompanyName", OleDbType.VarChar, 30, "CompanyName");

        connection.Open();

        DataSet custDS = new DataSet();
        adapter.Fill(custDS, "Customers");

        DataRow custRow = custDS.Tables["Customers"].NewRow();
        custRow["CustomerID"] = "NEWCO";
        custRow["CompanyName"] = "New Company";
        custDS.Tables["Customers"].Rows.Add(custRow);

        // add handlers
        adapter.RowUpdating += new OleDbRowUpdatingEventHandler(OnRowUpdating);
        adapter.RowUpdated += new OleDbRowUpdatedEventHandler(OnRowUpdated);

        adapter.Update(custDS, "Customers");

        // remove handlers
        adapter.RowUpdating -= new OleDbRowUpdatingEventHandler(OnRowUpdating);
        adapter.RowUpdated -= new OleDbRowUpdatedEventHandler(OnRowUpdated);

        foreach (DataRow row in custDS.Tables["Customers"].Rows)
        {
            if (row.HasErrors)
                Console.WriteLine(row.RowError);
        }
    }
}

protected static void OnRowUpdating(object sender,
    OleDbRowUpdatingEventArgs args)
{
    if (args.StatementType == StatementType.Insert)
    {
        System.IO.TextWriter writer = System.IO.File.AppendText("Inserts.log");
        writer.WriteLine("{0}: Customer {1} Inserted.",
            DateTime.Now, args.Row["CustomerID"]);
        writer.Close();
    }
}

protected static void OnRowUpdated(object sender, OleDbRowUpdatedEventArgs args)
{
    if (args.Status == UpdateStatus.ErrorsOccurred)
    {
        args.Row.RowError = args.Errors.Message;
        args.Status = UpdateStatus.SkipCurrentRow;
    }
}
Public Sub CreateDataAdapter(ByVal connectionString As String)
    Using connection As New OleDbConnection(connectionString)
        Dim adapter As New OleDbDataAdapter( _
            "SELECT * FROM Customers WHERE CustomerID = 'ALFKI'", connection)

        adapter.InsertCommand = New OleDbCommand( _
            "INSERT INTO Customers (CustomerID, CompanyName) VALUES(?, ?)", _
            connection)

        adapter.InsertCommand.Parameters.Add( _
            "@CustomerID", OleDbType.VarChar, 5, "CustomerID")
        adapter.InsertCommand.Parameters.Add( _
            "@CompanyName", OleDbType.VarChar, 30, "CompanyName")

        connection.Open()

        Dim custDS As New DataSet()
        adapter.Fill(custDS, "Customers")

        Dim custRow As DataRow = custDS.Tables("Customers").NewRow()
        custRow("CustomerID") = "NEWCO"
        custRow("CompanyName") = "New Company"
        custDS.Tables("Customers").Rows.Add(custRow)

        ' add handlers
        AddHandler adapter.RowUpdating, _
            New OleDbRowUpdatingEventHandler(AddressOf OnRowUpdating)
        AddHandler adapter.RowUpdated, _
            New OleDbRowUpdatedEventHandler(AddressOf OnRowUpdated)

        adapter.Update(custDS, "Customers")

        ' remove handlers
        RemoveHandler adapter.RowUpdating, _
            New OleDbRowUpdatingEventHandler(AddressOf OnRowUpdating)
        RemoveHandler adapter.RowUpdated, _
            New OleDbRowUpdatedEventHandler(AddressOf OnRowUpdated)

        Dim row As DataRow
        For Each row In custDS.Tables("Customers").Rows
            If row.HasErrors Then Console.WriteLine(row.RowError)
        Next
    End Using
End Sub

Sub OnRowUpdating(ByVal sender As Object, _
    ByVal args As OleDbRowUpdatingEventArgs)

    If args.StatementType = StatementType.Insert Then
        Dim writer As System.IO.TextWriter = _
            System.IO.File.AppendText("Inserts.log")
        writer.WriteLine("{0}: Customer {1} Inserted.", _
            DateTime.Now, args.Row("CustomerID"))
        writer.Close()
    End If
End Sub

Sub OnRowUpdated(ByVal sender As Object, _
    ByVal args As OleDbRowUpdatedEventArgs)

    If args.Status = UpdateStatus.ErrorsOccurred Then
        args.Row.RowError = args.Errors.Message
        args.Status = UpdateStatus.SkipCurrentRow
    End If
End Sub

Poznámky

Když použijete Update , dojde k aktualizaci dvou událostí na řádek dat.When you use Update, there are two events that occur per data row updated. Pořadí spuštění je následující:The order of execution is as follows:

  1. Hodnoty v DataRow jsou přesunuty do hodnot parametrů.The values in the DataRow are moved to the parameter values.

  2. OnRowUpdatingUdálost je vyvolána.The OnRowUpdating event is raised.

  3. Příkaz se spustí.The command executes.

  4. Pokud je příkaz nastaven na FirstReturnedRecord , první vrácený výsledek je umístěn v DataRow .If the command is set to FirstReturnedRecord, the first returned result is placed in the DataRow.

  5. Pokud existují výstupní parametry, jsou umístěny v DataRow .If there are output parameters, they are placed in the DataRow.

  6. OnRowUpdatedUdálost je vyvolána.The OnRowUpdated event is raised.

  7. AcceptChanges je volána.AcceptChanges is called.

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