unit3.pas

简单的图书馆查询系统

unit Unit3;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs,Unit1, Grids, DBGrids, StdCtrls, DB, DBTables;

type
  TForm3 = class(TForm)
    Edit1: TEdit;
    Button1: TButton;
    Label1: TLabel;
    DBGrid1: TDBGrid;
    Button2: TButton;
    RadioButton1: TRadioButton;
    RadioButton2: TRadioButton;
    RadioButton3: TRadioButton;
    RadioButton4: TRadioButton;
    DataSource1: TDataSource;
    Query1: TQuery;
    Label2: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form3: TForm3;

implementation

{$R *.dfm}

procedure TForm3.Button1Click(Sender: TObject);

begin
  if radiobutton3.Checked then
    begin
      Query1.Close;
      Query1.SQL.Clear;
      Query1.SQL.Add('select * from book');
      Query1.Open;
      end;

  if form3.RadioButton2.Checked then
    begin
      Query1.Close;
      Query1.SQL.Clear;
      Query1.SQL.Add('select * from book where 书名=:书名');
      Query1.ParamByName('书名').AsString:=edit1.Text;
      Query1.Open;
    end;

  if form3.RadioButton1.Checked then
    begin
      Query1.Close;
      Query1.SQL.Clear;
      Query1.SQL.Add('select * from book where 书号=:书号');
      Query1.ParamByName('书号').AsString:=edit1.Text;
      Query1.Open;
    end;

  if form3.RadioButton4.Checked then
    begin
      Query1.Close;
      Query1.SQL.Clear;
      Query1.SQL.Add('select * from book where 作者=:作者');
      Query1.ParamByName('作者').AsString:=edit1.Text;
      Query1.Open;
    end;
end;

procedure TForm3.Button2Click(Sender: TObject);
begin
form3.Close;
end;

end.