unit10.pas

这个是我自主研发的图书管理系统的应用

unit Unit10;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, StdCtrls, Grids, DBGrids, DB, ADODB, Menus;

type
  TForm10 = class(TForm)
    Panel1: TPanel;
    ADOConnection1: TADOConnection;
    ADOQuery1: TADOQuery;
    ADOQuery2: TADOQuery;
    ADOQuery3: TADOQuery;
    DataSource1: TDataSource;
    DataSource2: TDataSource;
    DBGrid1: TDBGrid;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    DBGrid2: TDBGrid;
    MainMenu1: TMainMenu;
    N1: TMenuItem;
    N2: TMenuItem;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure DBGrid2CellClick(Column: TColumn);
    procedure DBGrid1CellClick(Column: TColumn);
    procedure Button3Click(Sender: TObject);
    procedure N1Click(Sender: TObject);
    procedure N2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form10: TForm10;

implementation

uses Unit1;

var id,borrowId:string;
{$R *.dfm}

procedure TForm10.FormCreate(Sender: TObject);
begin
DBgrid1.Visible:=true;
Dbgrid2.Visible:=false;
button3.Enabled:=false;
end;

procedure TForm10.Button1Click(Sender: TObject);
var Querystr:string;
begin
   DBgrid2.Visible:=false;
   Dbgrid1.Visible:=true;
   Querystr:='select * from teacher,book,return1 where teacher.borrowbook_id=return1.borrowbook_id '
   +'and book.bookno=return1.bookno';
   adoquery1.Close;
   adoquery1.SQL.Clear;
   adoquery1.SQL.Text:=Querystr;
   adoquery1.Open;
end;

procedure TForm10.Button2Click(Sender: TObject);
var querystr:string;
begin
   DBgrid1.Visible:=false;
   Dbgrid2.Visible:=true;
   Querystr:='select * from student,book,return1 where student.borrowbook_id=return1.borrowbook_id '
   +'and book.bookno=return1.bookno';
   adoquery2.Close;
   adoquery2.SQL.Clear;
   adoquery2.SQL.Text:=Querystr;
   adoquery2.Open;
end;

procedure TForm10.DBGrid2CellClick(Column: TColumn);
begin
button3.Enabled:=true;
id:=adoquery2.fieldbyname('标识列').AsString;
borrowid:=adoquery2.fieldbyname('borrowbook_id').AsString;
end;

procedure TForm10.DBGrid1CellClick(Column: TColumn);
begin
   button3.Enabled:=true;
   id:=adoquery1.fieldbyname('标识列').AsString;
   borrowid:=adoquery1.fieldbyname('borrowbook_id').AsString;
end;

procedure TForm10.Button3Click(Sender: TObject);
begin
   case application.MessageBox(Pchar('确实要欲删除'+id+'号还书记录吗?'),'删除确认',MB_OKcancel+MB_ICONinformation) of
 IDCancel:;
 IDOK:
   begin
     adoquery3.Close;
     adoquery3.SQL.Clear;
     adoquery3.SQL.Add('select * from student where borrowbook_id=:id1');
     adoQuery3.Parameters.ParamByName('id1').Value:=borrowid;
     adoquery3.Open;
     if adoquery3.recordcount<>0 then
     begin
     DBgrid2.Visible:=false;
     Dbgrid1.Visible:=true;
     adoquery1.Close;
     adoquery1.SQL.Clear;
     adoquery1.SQL.Add('delete from return1 where 标识列='''+id+'''');
     adoquery1.ExecSQL;
    end
     else
      begin
         DBgrid1.Visible:=false;
         Dbgrid2.Visible:=true;
         adoquery2.Close;
         adoquery2.SQL.Clear;
         adoquery2.SQL.Add('delete from return1 where 标识列='''+id+'''');
         adoquery2.ExecSQL;
     end;
     application.MessageBox('删除记录成功!','成功',MB_OK+MB_ICONinformation);
   end;
  end;
end;

procedure TForm10.N1Click(Sender: TObject);
begin
  form10.Hide;
  animatewindow(form1.handle,1000,aw_Activate or aw_center);
  form1.Show;
end;

procedure TForm10.N2Click(Sender: TObject);
begin
application.Terminate;
end;

end.