TDataSetAfterCancel (Delphi)

Description

This example updates the form's status bar with a message when an AfterCancel event occurs. Set the status bar's SimplePanel property to True.

Code

procedure TForm1.Table1AfterCancel(DataSet: TDataSet);
begin
  StatusBar1.SimpleText := 'Record changes cancelled for ' + DataSet.Name;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  Table1.Cancel;
end;

procedure TForm1.Button3Click(Sender: TObject);
begin
  Table1.Post
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  i: Integer;

begin
  Table1:= TTable.Create(Form1);
  with Table1 do
  begin
    DatabaseName := 'DBDEMOS';
    TableType := ttParadox;
    TableName := 'CustInfo';
    Name := 'CustInfo';
    Table1.Active := False;

    { Do not overwrite an existing table. }
    if Table1.Exists then
    begin
        Table1.Close;
        Table1.DeleteTable;
    end;

    begin
      { The Table component must not be active. }
      { First, describe the type of table and give }
      { it a name. }
      { Next, describe the fields in the table. }
      with FieldDefs do
      begin
        Clear;
        with AddFieldDef do
        begin
          Name := 'Field1';
          DataType := ftInteger;
          Required := True;
        end;
        with AddFieldDef do
        begin
          Name := 'Field2';
          DataType := ftString;
          Size := 30;
        end;
      end;

     { Next, describe any indexes. }
      with IndexDefs do
      begin
        Clear;
        { The first index has no name because it is
        { a Paradox primary key. }
        with AddIndexDef do
        begin
          Name := '';
          Fields := 'Field1';
          Options := [ixPrimary];
        end;
        with AddIndexDef do
        begin
          Name := 'Fld2Indx';
          Fields := 'Field2';
          Options := [ixCaseInsensitive];
        end;
      end;
      { Call the CreateTable method to create the table. }
      CreateTable;
      Table1.Active:= True;
      for i := 1 to 20 do
        Table1.AppendRecord([i*111, i*222]);
    end;
  end;
  DS2.DataSet:= Table1;
  DBGrid2.DataSource.DataSet:= Table1;
  Table1.AfterCancel:= Table1AfterCancel;
  Table1.Active:= True;
end;

Uses

• Data.DB.TDataSet.AfterCancel ( fr | de | ja )