delrec.pas

delphi编写的图书管理系统,一般的管理系统

unit delrec;

interface

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

type
  Tdelfrm = class(TForm)
    PageControl1: TPageControl;
    TabSheet1: TTabSheet;
    TabSheet2: TTabSheet;
    BitBtn1: TBitBtn;
    GroupBox1: TGroupBox;
    r1: TRadioButton;
    r2: TRadioButton;
    Bevel1: TBevel;
    Label1: TLabel;
    Edit1: TEdit;
    ListView1: TListView;
    BitBtn2: TBitBtn;
    Label2: TLabel;
    GroupBox2: TGroupBox;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Edit2: TEdit;
    Edit3: TEdit;
    Edit4: TEdit;
    Label7: TLabel;
    Label8: TLabel;
    Label6: TLabel;
    Bevel2: TBevel;
    ListView2: TListView;
    procedure BitBtn1Click(Sender: TObject);
    procedure r1Click(Sender: TObject);
    procedure r2Click(Sender: TObject);
    procedure FormShow(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
    procedure TabSheet2Show(Sender: TObject);
  private
    { Private declarations }
  function checkbookno(b_no:string):boolean;//检查图书是否存在
  procedure listallbooks;//显示所有图书
  procedure delbook(b_no:string);//删除图书
  procedure booksumup;
  public
    { Public declarations }
  end;

var
  delfrm: Tdelfrm;

implementation
  uses main,global,newbook;
{$R *.dfm}
function Tdelfrm.checkbookno(b_no:string):boolean;
var t:Ttable;
begin
  t:=Ttable.Create(nil);
  t.DatabaseName :=dbname ;
  t.TableName :='book_info.db';
  t.Open;
  t.SetKey ;
  t.FieldByName('图书编号').AsString :=b_no ;
  if t.GotoKey then result:=true else result:=false;
  t.Close;
  t.Free ;
end;


procedure tdelfrm.listallbooks ;
var q:tquery;
begin
   q:=tquery.Create(nil);
   q.DatabaseName :=dbname ;
   q.SQL.Add('select * from book_info');
   q.Open;
   listview1.Items.Clear ;
   while not q.Eof do
   begin
   with listview1.Items.Add do
   begin
   caption:=q.fieldbyname('图书编号').AsString ;
   subitems.Add(q.fieldbyname('书名').AsString);
   subitems.Add(q.fieldbyname('作者').AsString);
   subitems.Add(q.fieldbyname('出版社').AsString);
   subitems.Add(datetostr(q.fieldbyname('出版时间').AsDateTime));
   subitems.Add(q.fieldbyname('类别').AsString);
   if isborrowed(caption) then subitems.Add('是') else subitems.Add('否');
   end;
   q.Next ;
   end;
   label2.Caption :='共'+inttostr(listview1.Items.Count)+'本';
   q.Close;
   q.Free;
end;

procedure tdelfrm.delbook(b_no:string);
var q:tquery;
begin
   q:=tquery.Create(nil);
   q.DatabaseName :=dbname ;
   q.SQL.Add('delete from book_info where 图书编号=:book_no');
   q.ParamByName('book_no').AsString :=b_no;
   q.ExecSQL ;
   messagedlg('成功删除！',mtinformation,[mbYes],0);
   q.Close;
   q.Free;
end;

procedure tdelfrm.booksumup ;
var q:tquery;
begin
   q:=tquery.Create(nil);
   q.DatabaseName :=dbname ;
   q.SQL.Add('select * from book_info');
   q.open ;
   edit2.Text :=inttostr(q.RecordCount);
   q.Close ;
   q.SQL.Clear ;
   q.SQL.Add('select * from borrow_info');
   q.open ;
   edit3.Text :=inttostr(q.RecordCount);
   edit4.Text :=inttostr(strtoint(edit2.Text)-strtoint(edit3.Text));
   q.Close;
   q.SQL.Clear ;
   q.SQL.Add('select 类别,count(类别) as 藏书总数 from book_info group by 类别');
   q.Open ;
   listview2.Items.Clear ;
   while not q.Eof do
   begin
   with listview2.Items.Add do
   begin
   caption:=q.fieldbyname('类别').AsString ;
   subitems.Add(inttostr(q.fieldbyname('藏书总数').AsInteger));
   end;
   q.Next ;
   end;
   q.Close;
   q.Free ;
end;

procedure Tdelfrm.BitBtn1Click(Sender: TObject);
begin
close;
end;

procedure Tdelfrm.r1Click(Sender: TObject);
begin
if r1.Checked then
   begin
   edit1.Enabled :=true;
   edit1.Color :=clwindow;
   listview1.Enabled :=false;
   listview1.Color :=clbtnface;
   end;
end;

procedure Tdelfrm.r2Click(Sender: TObject);
begin
if r2.Checked then
   begin
   edit1.Enabled :=false;
   edit1.Color :=clinfobk;
   listview1.Enabled :=true;
   listview1.Color :=clwindow;
   end;
end;

procedure Tdelfrm.FormShow(Sender: TObject);
begin
listallbooks;
end;

procedure Tdelfrm.BitBtn2Click(Sender: TObject);
var  b_no:string;
     ch:integer;
begin
if r1.Checked then
  if checkbookno(edit1.Text) then b_no:=edit1.Text
  else
     begin
     messagedlg('图书不存在！',mtError,[mbYes],0);
     exit;
     end;
if r2.Checked then
  if listview1.Selected=nil then exit
  else b_no:=listview1.Selected.Caption ;
if isborrowed(b_no)then
   begin
   messagedlg('该图书处于借出状态，不能删除！',mtWarning,[mbYes],0);
   exit;
   end;
ch:=messagedlg('确认删除图书吗？',mtconfirmation,[mbYes,mbNo],0);
if ch=mrNo then exit;
delbook(b_no);
listallbooks;//更新列表
end;

procedure Tdelfrm.TabSheet2Show(Sender: TObject);
begin
booksumup;
end;

end.