TCustomClientDataSet.AfterCancel Event

Occurs after an application completes a request to cancel modifications to the active record.

Pascal

property AfterCancel: TDataSetNotifyEvent;

C++

__property TDataSetNotifyEvent AfterCancel;

Description

Write an AfterCancel event handler to take specific action after an application cancels changes to the active record. AfterCancel is called by the Cancel method after it updates the current position, releases the lock on the active record if necessary, and sets the dataset state to dsBrowse. If an application requires additional processing before returning control to a user after a Cancel event, code it in the AfterCancel event.

Delphi Examples:

Copy Code

{
This example updates the form’s status bar with a message when an AfterCancel event occurs.
} 
procedure TForm1.Table1AfterCancel(DataSet: TDataSet);
begin
  StatusBar1.SimpleText := 'Record changes cancelled for ' + DataSet.Name;
end;

Copy Code

{
This example updates the form’s status bar with a message
when an AfterCancel event occurs.  Set the StatusBar
SimplePanel property to True.
}
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;
    { Don't 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 1st 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;