consumeundo.~pas

结于初学者来说这对数据库是一个很好的例子

unit consumeundo;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Mask, DB, DBTables;

type
  TForm15 = class(TForm)
    Label1: TLabel;
    Q_qx: TQuery;
    GroupBox1: TGroupBox;
    Label9: TLabel;
    Label2: TLabel;
    Label5: TLabel;
    Label8: TLabel;
    Label7: TLabel;
    Label6: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    qxsl: TMaskEdit;
    Button1: TButton;
    Button2: TButton;
    Label10: TLabel;
    Q_zj: TQuery;
    procedure Button2Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form15: TForm15;

implementation

uses main;

{$R *.dfm}

procedure TForm15.Button2Click(Sender: TObject);
begin
 close;
end;

procedure TForm15.Button1Click(Sender: TObject);
 var RestCount:integer;
begin
 if (length(trim(qxsl.Text))=0) or (StrToInt(trim(qxsl.Text))>StrToInt(label8.Caption)) then
  begin
   MessageDlg('您输入错误，请重新输入！',mtError,[mbok],0);
   end
  else
   begin
//更改数量
  Q_qx.SQL.Clear;
  Q_qx.SQL.Add('select * from DinList where RoomName='''+label10.Caption+'''');
  Q_qx.SQL.Add('and MenuName='''+label6.Caption+'''');
  Q_qx.Open;
  Q_qx.Edit;
  Q_qx['Quantity']:=Q_qx['Quantity']-StrToInt(trim(qxsl.Text));
  Q_qx.Post;
  Q_qx.SQL.Clear;
  Q_qx.SQL.Add('delete from DinList where Quantity<=0');
  q_qx.ExecSQL;
//判断商品如果允许库存则库存增加相应的减少数量
  Q_zj.sql.clear;
  Q_zj.sql.add('select * from Menu where MenuNo='''+label5.caption+'''');
  Q_zj.open;
  if  Q_zj['kc']='是' then
   begin
     Q_zj.close;
     Q_zj.sql.clear;
     Q_zj.sql.add('select * from kucun where MenuNo='''+label5.caption+'''');
     Q_zj.open;
     RestCount:=Q_zj.FieldbyName('sl').asinteger+StrToInt(Trim(qxsl.text));
     Q_zj.edit;
     Q_zj['sl']:=RestCount;
     Q_zj.post;
     Q_zj.close;
   end;
//结束 
  Form15.Close;
  end;
end;

procedure TForm15.FormClose(Sender: TObject; var Action: TCloseAction);
begin
    form1.Q_selected.close;
    form1.Q_selected.open;
end;

procedure TForm15.FormCreate(Sender: TObject);
begin
  qxsl.EditMask:='99;1; ';
end;

end.