unit3.~pas

实现图书馆数据库管理功能

unit Unit3;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, jpeg, ExtCtrls, StdCtrls, ComCtrls, Menus,  ImgList, Buttons;

type
  TForm3 = class(TForm)
    Edit1: TEdit;
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    Label2: TLabel;
    Image_title: TImage;
    Image_close: TImage;
    Image1: TImage;
    Label1: TLabel;
    Image2: TImage;

    procedure FormCreate(Sender: TObject);



    procedure d1Click(Sender: TObject);


   procedure wmgetminmaxinfo(var message:twmgetminmaxinfo);
    message wm_getminmaxinfo;
    procedure BitBtn1Click(Sender: TObject);
    procedure BitBtn1Enter(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
    procedure FormShow(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure Image_closeClick(Sender: TObject);
   
  private

    { Private declarations }
    originalpos:tpoint;
    currentpos:tpoint;
    downpos:tpoint;
    mouselbuttondown:boolean;
    originalwid,originalhei:integer;
    flag:string;
    flag_normal:boolean;
     public
     
     readerno:string;
    { Public declarations }
  end;

var
  Form3: TForm3;


implementation

uses unit2;

{$R *.dfm}











procedure TForm3.FormCreate(Sender: TObject);

begin
self.DefaultMonitor:= dmdesktop;
flag_normal:=true;
mouselbuttondown:=false;
end;




procedure TForm3.d1Click(Sender: TObject);
begin
self.WindowState:=wsnormal;
flag_normal:=true;
end;

procedure tForm3.wmgetminmaxinfo(var message:twmgetminmaxinfo);
var f:integer;
begin
with message.MinMaxInfo^ do
begin
f:=GetSystemMetrics(SM_CYSCREEN);
ptmaxsize.y:=f-28;
ptmaxposition.x:=0;
ptmaxposition.Y:=0;
end;
message.Result:=0;
inherited;
end;

procedure TForm3.BitBtn1Click(Sender: TObject);
var
hasno,allowno:integer;
flag:boolean;
begin
flag:=true;
if edit1.Text='' then
begin
application.MessageBox('      请输入读者编号       ', '提示',MB_OK,);
end
else
begin
form2.Table1.Filter:='读者编号='''+edit1.text+'''';
form2.Table1.Filtered:=true;
form2.Table1.Active:=true;
if form2.Table1.RecordCount=0 then
messagedlg('此读者编号不存在,请重新输入',mtwarning,[mbok],0)
else if form2.Table1.RecordCount>0 then
begin
readerno:=edit1.text;
form2.Edit2.Text:=form2.Table1.fieldbyname('读者编号').value;
form2.Edit3.Text:=form2.Table1.fieldbyname('姓名').value;

form2.Edit4.Text:=form2.Table3.fieldbyname('类型名称').value;


//此处为是否已借满的代码
hasno:=form2.table1.FieldByName('已借册数').AsInteger;
form2.table3.Active:=true;
allowno:=form2.table3.FieldByName('借出册数').AsInteger;
form2.Enabled:=true;
form2.Label15.Visible:=true;
form2.DBText1.Visible:=true;

if hasno>=allowno then
begin
  form2.f_chaoce:=true;
  MessageDlg('您的图书可借册数已满，请归还图书之后再借！', mtwarning,[mbOk], 0);
  form2.edit1.Enabled:=false;
  form2.SpeedButton7.Enabled:=false;
end;
form2.checkoveredbook();
form2.showhowmanybooks();

if form2.Edit1.Enabled then
begin
  form2.Edit1.SetFocus;
  form2.Edit1.SelStart:=0;
  form2.Edit1.SelLength:=length(form2.edit1.text);
end;

close;
if (not form2.f_chaoqi) and (not form2.f_chaoce) then
   form2.Edit1.Enabled:=true;
   flag:=false;
end;
if flag then
  begin
    form3.Edit1.SetFocus;
    form3.Edit1.SelStart:=0;
    form3.Edit1.SelLength:=length(form3.edit1.text);
  end;
end;
end;

procedure TForm3.BitBtn1Enter(Sender: TObject);
begin
bitbtn1click(sender)
end;


procedure TForm3.BitBtn2Click(Sender: TObject);
begin
if form2.Edit2.Text='' then
form2.edit1.Enabled:=false;
close;
end;

procedure TForm3.FormShow(Sender: TObject);
begin
form2.Enabled:=false;
end;

procedure TForm3.FormClose(Sender: TObject; var Action: TCloseAction);
begin
 form2.Enabled:=true;
end;

procedure TForm3.Image_closeClick(Sender: TObject);
begin
close;
end;

end.