Delphi/CppBuilder

开发平台：
Delphi

lend.pas：源码内容
							unit lend;
interface
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, DBCtrls, Mask, DB, DBTables, data, ownbook;
type
  Tlendform = class(TForm)
    GroupBox1: TGroupBox;
    StaticText9: TStaticText;
    ComboBox1: TComboBox;
    StaticText10: TStaticText;
    DBName: TDBEdit;
    StaticText11: TStaticText;
    DBAuthor: TDBEdit;
    StaticText12: TStaticText;
    DBPress: TDBEdit;
    StaticText13: TStaticText;
    DBOutDate: TDBEdit;
    StaticText14: TStaticText;
    DBCost: TDBEdit;
    StaticText15: TStaticText;
    DBMemo: TDBMemo;
    GroupBox2: TGroupBox;
    StaticText1: TStaticText;
    StaticText2: TStaticText;
    StaticText3: TStaticText;
    StaticText4: TStaticText;
    StaticText5: TStaticText;
    ReaderIDEdit: TEdit;
    TotalEdit: TEdit;
    OwnTimeEdit: TEdit;
    FineEdit: TEdit;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    tempADOQuery1: TQuery;
    TEMPADOQuery2: TQuery;
    DataSource1: TDataSource;
    procedure FormShow(Sender: TObject);
    procedure ComboBox1Change(Sender: TObject);
    procedure ComboBox1KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure ReaderIDEditChange(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
type
   TOwnBook = record
      code:string;
      name:string;
      price:string;
      owndays:integer;
    end;
var
  lendform: Tlendform;
implementation
{$R *.dfm}
procedure Tlendform.FormShow(Sender: TObject);
var
  i:integer;
begin
  with datamoduleado.ADOQuery1 do
  begin
    sql.Clear ;
    sql.Add('select code from book');
    open;
    first;
    for i:=0 to recordcount-1 do
    begin
      combobox1.Items.Add(fieldbyname('code').AsString );
      next;
    end;
    close;
  end;
end;
procedure Tlendform.ComboBox1Change(Sender: TObject);
var
  fdate:tdate;
  owntime:Tdate;
begin
  readeridedit.Text :='';
  totaledit.Text :='';
  owntimeedit.Text :='';
  fineEdit.Text :='';
  if length(combobox1.Text )=10 then
  begin
    try
       with datamoduleado.ADOTable1 do
       begin
         tablename:='book';
         dbname.DataField :='name';
         dbauthor.DataField :='author';
         dbpress.DataField :='press';
         dboutdate.DataField :='outdate';
         dbcost.DataField :='cost';
         dbmemo.DataField :='memo0';
         active:=true;
         if not locate('code',combobox1.Text ,[]) then
         begin
           messagedlg('没有数据或数据库操作失败',mterror,[mbok],0);
           exit;
         end;
       end;
    except
      messagedlg('数据操作出错',mterror,[mbok],0);
    end;
    try
      with datamoduleado.ADOQuery1 do
      begin
        sql.Clear ;
        sql.Add('select * from lend where code=:code');
        parameters.ParamByName('code').Value :=combobox1.Text;
        open;
        if recordcount<>0 then
        begin
          fdate:=fieldbyname('outdate').AsDateTime ;
          owntime:=date-fdate;
          owntimeedit.Text :=floattostr(owntime);
          readerIDEdit.Text :=fieldbyname('readerid').AsString;
          statictext1.Visible :=true;
          owntimeedit.Visible :=true;
          if strtoint(owntimeedit.Text )>60 then
          begin
            statictext12.Visible :=true;
            fineedit.Visible :=true;
            fineedit.Text :=floattostr((strtoint(owntimeedit.Text )-60)*0.1);
          end;
          button1.Enabled :=false;
          button2.Enabled :=true;
          button2.SetFocus ;
          close;
        end
        else  begin
                readeridedit.SetFocus ;
                button1.Enabled :=true;
                button2.Enabled :=false;
              end;
        end;
      except
        readeridedit.SetFocus ;
      end;
    end;
end;
procedure Tlendform.ComboBox1KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
  if key=13 then
    combobox1change(sender);
end;
procedure Tlendform.ReaderIDEditChange(Sender: TObject);
begin
  if length(readerIDEdit.Text )=10 then
  begin
    with datamoduleADO.ADOQuery1 do
    begin
      sql.Clear ;
      sql.Add('select readerid from reader where readerid=:readerid');
      parameters.ParamByName('readerid').Value :=readeridedit.Text ;
      open;
      if recordcount=0 then
      begin
        button1.Enabled :=false;
        messagedlg('借书证号<'+readeridedit.Text +'>不存在',mterror,[mbok],0);
        close;
        exit;
      end;
      close;
    end;
    try
      with datamoduleado.ADOQuery1 do
      begin
        sql.Clear ;
        sql.Add('select count(readerid) from lend where readerid=:readerid');
        parameters.ParamByName('readerid').Value :=readeridedit.Text ;
        open;
        totaledit.Text :=inttostr(fields[0].Value );
        close;
      end;
    except
      totaledit.Text :='0';
    end;
    button2.Enabled :=false;
    button1.Enabled :=true;
    button1.SetFocus ;
  end;
end;
procedure Tlendform.Button1Click(Sender: TObject);
var
  tempownbook:townbook;
  canlend:boolean;
  mmcode:string;
begin
  if readeridedit.Text <>'' then
  begin
  try
    with datamoduleado.adoquery1 do
    begin
      sql.clear;
      sql.Add('select code from lend where readerid=:readerid');
      parameters.ParamByName('readerid').Value :=readeridedit.Text ;
      open;
      canlend:=true;
      ownbookform.ListView1.Items.Clear ;
      mmcode:=fieldbyname('code').AsString;
      while not eof do
      begin
        with tempadoquery1 do
        begin
        sql.Clear ;
        sql.Add('select * from book where code =:code') ;
        parameters.ParamByName('code').Value :=mmcode;
        open;
        tempownbook.code:=fieldbyname('code').asstring;
        tempownbook.name:=fieldbyname('name').asstring;
        tempownbook.price:=fieldbyname('cost').asstring;
        try
         with tempadoquery2 do
         begin
           sql.Clear ;
           sql.Add('select * from lend where code=:code and readerid=:readerid');
           parameters.ParamByName('code').Value :=datamoduleado.ADOQuery1.fieldbyname('code').AsString ;
           parameters.ParamByName('readerid').Value := readeridedit.Text ;
           open;
           tempownbook.owndays:=round(date-fieldbyname('outdate').AsDateTime );
           close;
         end;
        except
           tempownbook.owndays:=0;
        end;
        close;
      end;
      if tempownbook.owndays>60 then
      begin
        with ownbookform.listview1.Items.add do
        begin
         caption:=tempownbook.code;
         subitems.add(tempownbook.name);
         subitems.add(tempownbook.price);
         subitems.Add(inttostr(tempownbook.owndays));
         subitems.Add(floattostr((tempownbook.owndays-60)*0.1));
        end;
        canlend:=false;
      end;
    next;
  end;
    close;
  end;
except
 canlend:=true;
end;
if canlend=false then
begin
  ownbookform.Caption :=readeridedit.text+'有以下书籍没按时归还';
  ownbookform.showmodal;
  exit;
end;
try
  with DatamoduleADO.adoquery1 do
  begin
    sql.clear;
    sql.add('insert into lend(code,readerid,outdate)'+' values(:code,:readerid,:outdate)');
    parameters.parambyname('code').value:=combobox1.text;
    parameters.parambyname('readerid').value:=readeridedit.text;
    parameters.parambyname('outdate').value:=datetostr(now());
    execsql;
  end;
except
  messagedlg('借书不成功',mterror,[mbok],0);
end;
end
else begin
        showmessage('请输入借书证号！');
        readeridedit.setfocus;
     end;
end;
procedure Tlendform.Button2Click(Sender: TObject);
begin
  try
    with datamoduleado.adoquery1 do
    begin
      sql.clear;
      sql.add('delete from lend where code=:code');
      parameters.parambyname('code').value:=combobox1.text;
      execsql;
      close;
    end;
  except
    messagedlg('还书不成功',mterror,[mbok],0);
  end;
  readeridedit.text:='';
  totaledit.text:='';
  owntimeedit.text:='';
  fineedit.text:='';
end;
procedure Tlendform.Button3Click(Sender: TObject);
begin
  close;
end;
end.

						