unit6.pas

用于开发税务票据管理的软件

unit Unit6;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs,unit5,db, ADODB;

type
  TForm6 = class(TForm5)
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form6: TForm6;

implementation

{$R *.dfm}
procedure TForm6.FormCreate(Sender: TObject);
begin
Button1.Caption:='统计';
button2.Show;
button3.Show;
end;
procedure tform6.Button1Click(Sender: TObject);
var worth:double;
st:string;
begin
inherited;

worth:=0;   //求表中进价总和。
db1.First;
while not db1.Eof do
begin
worth:=worth+db1.FieldValues['进价'];
db1.Next;
end;
st:=#13+'这些总价值为:'+floattostr(worth)+#13;

messagedlg('统计结果如下:'+#13+'共有:'+inttostr(db1.RecordCount)+'台'+st,mtinformation,[mbok],0);
end;
end.