Metodo SqlCeResultSet.Update

Articolo
05/27/2011

Invia le modifiche dal record corrente alla riga sottostante sul server.

Spazio dei nomi System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (in System.Data.SqlServerCe.dll)

Sintassi

'Dichiarazione
Public Sub Update
'Utilizzo
Dim instance As SqlCeResultSet

instance.Update()

public void Update()

public:
void Update()

member Update : unit -> unit

public function Update()

Osservazioni

Se la funzione viene chiamata su un reader non aggiornabile o se il reader non è posizionato su un record valido, viene generata un'eccezione InvalidOperation.

Esempi

Dim conn As SqlCeConnection = Nothing

Try
    File.Delete("Test.sdf")

    Dim engine As New SqlCeEngine("Data Source = Test.sdf")
    engine.CreateDatabase()

    conn = New SqlCeConnection("Data Source = Test.sdf")
    conn.Open()

    Dim cmd As SqlCeCommand = conn.CreateCommand()
    cmd.CommandText = "CREATE TABLE myTable (col1 INT)"
    cmd.ExecuteNonQuery()

    cmd.CommandText = "SELECT * FROM myTable"

    Dim rs As SqlCeResultSet = cmd.ExecuteResultSet(ResultSetOptions.Updatable Or ResultSetOptions.Scrollable)

    Dim rec As SqlCeUpdatableRecord = rs.CreateRecord()

    ' Insert 10 records
    '
    Dim i As Integer
    For i = 0 To 9
        rec.SetInt32(0, i)
        rs.Insert(rec)
    Next i

    ' Update the 5th record
    '
    If True = rs.ReadAbsolute(5) Then
        rs.SetInt32(0, 55)
        rs.Update()
    End If

    ' Delete the 2nd record
    '
    If True = rs.ReadAbsolute(2) Then
        rs.Delete()
    End If
Catch e As Exception
    MessageBox.Show(e.Message)
Finally
    conn.Close()
End Try

SqlCeConnection conn = null;

try
{
    File.Delete("Test.sdf");

    SqlCeEngine engine = new SqlCeEngine("Data Source = Test.sdf");
    engine.CreateDatabase();

    conn = new SqlCeConnection("Data Source = Test.sdf");
    conn.Open();

    SqlCeCommand cmd = conn.CreateCommand();
    cmd.CommandText = "CREATE TABLE myTable (col1 INT)";
    cmd.ExecuteNonQuery();

    cmd.CommandText = "SELECT * FROM myTable";

    SqlCeResultSet rs = cmd.ExecuteResultSet(ResultSetOptions.Updatable |
        ResultSetOptions.Scrollable);

    SqlCeUpdatableRecord rec = rs.CreateRecord();

    // Insert 10 records
    //
    for (int i = 0; i < 10; i++)
    {
        rec.SetInt32(0, i);
        rs.Insert(rec);
    }

    // Update the 5th record
    //
    if (true == rs.ReadAbsolute(5))
    {
        rs.SetInt32(0, 55);
        rs.Update();
    }

    // Delete the 2nd record
    //
    if (true == rs.ReadAbsolute(2))
    {
        rs.Delete();
    }
}
catch (Exception e)
{
    MessageBox.Show(e.Message);
}
finally
{
    conn.Close();
}

Vedere anche

Riferimento

SqlCeResultSet Classe

Spazio dei nomi System.Data.SqlServerCe

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