Proprietà SqlCeDataAdapter.InsertCommand

Ottiene o imposta un'istruzione SQL utilizzata per inserire nuovi record nell'origine dati.

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

Sintassi

'Dichiarazione
Public Property InsertCommand As SqlCeCommand
    Get
    Set
'Utilizzo
Dim instance As SqlCeDataAdapter
Dim value As SqlCeCommand

value = instance.InsertCommand

instance.InsertCommand = value

public SqlCeCommand InsertCommand { get; set; }

public:
property SqlCeCommand^ InsertCommand {
    SqlCeCommand^ get ();
    void set (SqlCeCommand^ value);
}

member InsertCommand : SqlCeCommand with get, set

function get InsertCommand () : SqlCeCommand
function set InsertCommand (value : SqlCeCommand)

Valore proprietà

Tipo: System.Data.SqlServerCe.SqlCeCommand
Oggetto SqlCeCommand utilizzato durante l'applicazione del metodo Update per inserire record nell'origine dati che corrispondono alle nuove righe nell'oggetto DataSet.

Osservazioni

Durante una chiamata al metodo Update, se la proprietà non è impostata e sono presenti informazioni sulla chiave primaria nell'oggetto DataSet, la proprietà InsertCommand potrà essere generata automaticamente se si imposta la proprietà SelectCommand e si utilizza l'oggetto SqlCeCommandBuilder. In seguito, qualsiasi comando aggiuntivo non impostato viene generato dalla classe SqlCeCommandBuilder. Questa logica di generazione richiede la presenza di informazioni sulle colonne di chiave primaria nell'oggetto DataSet.

Quando la proprietà InsertCommand viene assegnata a un oggetto SqlCeCommand precedentemente creato, l'oggetto SqlCeCommand non verrà duplicato. La proprietà InsertCommand conserva un riferimento all'oggetto SqlCeCommand creato in precedenza.

Esempi

Nell'esempio seguente viene creata una classe SqlCeDataAdapter e ne vengono impostate alcune proprietà.

Dim cmd As SqlCeCommand = Nothing
Dim adp As SqlCeDataAdapter = Nothing

Try
    adp = New SqlCeDataAdapter()
    Dim conn As New SqlCeConnection("Data Source = MyDatabase.sdf")

    ' Create the SelectCommand
    '
    cmd = conn.CreateCommand()
    cmd.CommandText = "SELECT [Employee ID], [First Name], [Last Name] FROM Employees"
    adp.SelectCommand = cmd

    ' Create the InsertCommand
    '
    cmd = conn.CreateCommand()
    cmd.CommandText = "INSERT INTO Employees ([First Name],[Last Name]) VALUES (@first, @last)"

    Dim p As SqlCeParameter = Nothing

    p = cmd.Parameters.Add("@first", SqlDbType.NVarChar, 10, "First Name")
    p.SourceVersion = DataRowVersion.Original

    p = cmd.Parameters.Add("@last", SqlDbType.NVarChar, 20, "Last Name")
    p.SourceVersion = DataRowVersion.Original

    adp.InsertCommand = cmd

    ' Create the UpdateCommand
    '
    cmd = conn.CreateCommand()
    cmd.CommandText = "UPDATE Employees SET [First Name] = @first, " + _
        "[Last Name] = @last WHERE [Employee ID] = @employeeID"

    p = cmd.Parameters.Add("@first", SqlDbType.NVarChar, 10, "First Name")
    p.SourceVersion = DataRowVersion.Current

    p = cmd.Parameters.Add("@last", SqlDbType.NVarChar, 20, "Last Name")
    p.SourceVersion = DataRowVersion.Current

    p = cmd.Parameters.Add("@employeeID", SqlDbType.NVarChar, 20, "Employee ID")
    p.SourceVersion = DataRowVersion.Original

    adp.UpdateCommand = cmd

    ' Populate the dataset with the results from the SELECT statement
    '
    Dim ds As New DataSet()
    adp.Fill(ds)

    ' Modify the dataset
    '
    MessageBox.Show("Number of rows: " & ds.Tables(0).Rows.Count)

    ' Insert some rows
    '
    ds.Tables(0).Rows.Add(New Object() {Nothing, "Barbara", "Decker"})
    ds.Tables(0).Rows.Add(New Object() {Nothing, "Joe", "Clayton"})

    ' Update some rows
    '
    ds.Tables(0).Rows(1)(1) = "David"
    ds.Tables(0).Rows(1)(2) = "Johnson"

    ' This will execute two INSERT and one UPDATE statements
    '
    adp.Update(ds.Tables(0))
Catch e As Exception
    MessageBox.Show(e.Message)
Finally
    If Not Nothing Is adp.SelectCommand Then
        adp.SelectCommand.Dispose()
    End If
    If Not Nothing Is adp.InsertCommand Then
        adp.InsertCommand.Dispose()
    End If
End Try

SqlCeCommand cmd = null;
SqlCeDataAdapter adp = null;

try
{
    adp = new SqlCeDataAdapter();
    SqlCeConnection conn = new SqlCeConnection("Data Source = MyDatabase.sdf");

    // Create the SelectCommand
    //
    cmd = conn.CreateCommand();
    cmd.CommandText = "SELECT [Employee ID], [First Name], [Last Name] FROM Employees";
    adp.SelectCommand = cmd;

    // Create the InsertCommand
    //
    cmd = conn.CreateCommand();
    cmd.CommandText = "INSERT INTO Employees ([First Name],[Last Name]) VALUES (@first, @last)";

    SqlCeParameter p = null;

    p = cmd.Parameters.Add("@first", SqlDbType.NVarChar, 10, "First Name");
    p.SourceVersion = DataRowVersion.Original;

    p = cmd.Parameters.Add("@last", SqlDbType.NVarChar, 20, "Last Name");
    p.SourceVersion = DataRowVersion.Original;

    adp.InsertCommand = cmd;

    // Create the UpdateCommand
    //
    cmd = conn.CreateCommand();
    cmd.CommandText = "UPDATE Employees SET [First Name] = @first, " +
        "[Last Name] = @last WHERE [Employee ID] = @employeeID";

    p = cmd.Parameters.Add("@first", SqlDbType.NVarChar, 10, "First Name");
    p.SourceVersion = DataRowVersion.Current;

    p = cmd.Parameters.Add("@last", SqlDbType.NVarChar, 20, "Last Name");
    p.SourceVersion = DataRowVersion.Current;

    p = cmd.Parameters.Add("@employeeID", SqlDbType.NVarChar, 20, "Employee ID");
    p.SourceVersion = DataRowVersion.Original;

    adp.UpdateCommand = cmd;

    // Populate the dataset with the results from the SELECT statement
    //
    DataSet ds = new DataSet();
    adp.Fill(ds);

    // Modify the dataset
    //
    MessageBox.Show("Number of rows: " + ds.Tables[0].Rows.Count);

    // Insert some rows
    //
    ds.Tables[0].Rows.Add(new object[] { null, "Barbara", "Decker" });
    ds.Tables[0].Rows.Add(new object[] { null, "Joe", "Clayton" });

    // Update some rows
    //
    ds.Tables[0].Rows[1][1] = "David";
    ds.Tables[0].Rows[1][2] = "Johnson";

    // This will execute two INSERT and one UPDATE statements 
    //
    adp.Update(ds.Tables[0]);


}
catch (Exception e)
{
    MessageBox.Show(e.Message);
}
finally
{
    if (null != adp.SelectCommand) adp.SelectCommand.Dispose();
    if (null != adp.InsertCommand) adp.InsertCommand.Dispose();
}

Vedere anche

Riferimento

SqlCeDataAdapter Classe

Spazio dei nomi System.Data.SqlServerCe

DeleteCommand

SelectCommand

UpdateCommand