SqlRowUpdatingEventArgs Класс

Определение

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

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

type SqlRowUpdatingEventArgs = class
    inherit RowUpdatingEventArgs

Public NotInheritable Class SqlRowUpdatingEventArgs
Inherits RowUpdatingEventArgs

Наследование

Object

EventArgs

RowUpdatingEventArgs

SqlRowUpdatingEventArgs

Примеры

В следующем примере показано, как использовать события RowUpdating и RowUpdated .

Событие RowUpdating возвращает следующие выходные данные:

аргументы event: (command=System.Data.SqlClient.SQLCommand commandType=2 status=0)

Событие RowUpdated возвращает следующие выходные данные:

аргументы event: (command=System.Data.SqlClient.SQLCommand commandType=2 recordsAffected=1 row=System.Data.DataRow[37] status=0)

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

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

public static int Main()
{
    const string CONNECTION_STRING = "Persist Security Info=False;Integrated Security=SSPI;database=northwind;server=mySQLServer";
    const string SELECT_ALL = "select * from Products";

    //Create DataAdapter.
    SqlDataAdapter rAdapter    = new SqlDataAdapter(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] = "new product";

    //Add handlers.
    rAdapter.RowUpdating += new SqlRowUpdatingEventHandler( OnRowUpdating );
    rAdapter.RowUpdated += new SqlRowUpdatedEventHandler( OnRowUpdated );

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

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

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

private static void PrintEventArgs(SqlRowUpdatedEventArgs 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 SqlRowUpdatingEventArgs)
    PrintEventArgs(e)
End Sub 

'Handler for RowUpdated event.
Private Shared Sub OnRowUpdated(sender As Object, e As SqlRowUpdatedEventArgs)
    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 = "Persist Security Info=False;Integrated Security=SSPI;database=northwind;server=mySQLServer"
    Const SELECT_ALL As String = "select * from Products"
    
    'Create DataAdapter.
    Dim rAdapter As New SqlDataAdapter(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) = "new product"
    
    '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 

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

Комментарии

Событие RowUpdating вызывается перед до Update строки.

При использовании Updateпроисходит два события для каждой обновленной строки данных. Порядок выполнения выглядит следующим образом:

1. Значения в перемещаются DataRow в значения параметров.

2. Возникает событие OnRowUpdating.

3. Команда выполняется.

4. Если для команды задано значение FirstReturnedRecord, а первый возвращенный результат помещается в DataRow.

5. Если есть выходные параметры, они помещаются в DataRow.

6. Возникает событие OnRowUpdated.

7. Вызывается метод AcceptChanges.

Конструкторы

Свойства

Методы

Применяется к

См. также раздел

• Общие сведения об ADO.NET