Aggregates (Delphi)

Note

This demo is available in your FlexCel installation at <FlexCel Install Folder>\Demo\Delphi\Modules\20.Reports\46.Aggregates and also at https:​//​github.​com/​tmssoftware/​TMS-​FlexCel.​VCL-​demos/​tree/​master/​Delphi/​Modules/​20.​Reports/​46.​Aggregates

Overview

FlexCel allows you to aggregate tables on the fly, providing you with the sum, average, maximum or minimum of the records in a table.

Note

You will normally not want to use in-memory aggregates, since they are slower and consume more memory than aggregates made directly in the database. (using an expression like "select sum(field1) from table group by field2")

Concepts

• Different ways to use the <#aggregate> tag to aggregate the values in a table.

Files

UMainForm.pas

unit UMainForm;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics,
  FlexCel.VCLSupport, FlexCel.Core, FlexCel.XlsAdapter, FlexCel.Report, FlexCel.Render,
  {$if CompilerVersion >= 23.0} System.UITypes, {$IFEND}
  ShellApi,
  Controls, Forms, Dialogs, StdCtrls, ExtCtrls;

type
  TMainForm = class(TForm)
    btnCancel: TButton;
    btnGo: TButton;
    SaveDialog: TSaveDialog;
    Label1: TLabel;
    procedure btnCancelClick(Sender: TObject);
    procedure btnGoClick(Sender: TObject);
  private
    procedure RunReport;
    function GetDataPath: string;
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

implementation
uses IOUtils, DemoProducts;

{$R *.dfm}

procedure TMainForm.btnCancelClick(Sender: TObject);
begin
  Close;
end;

procedure TMainForm.btnGoClick(Sender: TObject);
begin
  RunReport;

end;

function TMainForm.GetDataPath: string;
begin
  Result := TPath.Combine(TPath.GetDirectoryName(ParamStr(0)), '..\..');
end;


procedure TMainForm.RunReport;
var
  Report: TFlexCelReport;
begin
  if not SaveDialog.Execute then exit;

  Report := TFlexCelReport.Create(true);
  try
    //For this demo, instead of adding the full datamodule, we'll add the tables we need only.
    Report.AddTable('Products', DemoTables.Products);
    Report.AddTable('Order Details', DemoTables.OrderDetails);
    Report.Run(
      TPath.Combine(GetDataPath, 'Aggregates.template.xls'),
      SaveDialog.FileName);
  finally
    Report.Free;
  end;

  if MessageDlg('Do you want to open the generated file?', mtConfirmation, [mbYes, mbNo], 0) = mrYes then
  begin
    ShellExecute(0, 'open', PCHAR(SaveDialog.FileName), nil, nil, SW_SHOWNORMAL);
  end;


end;

end.