unit1.pas

Delphi函数参考大全的CD

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    ADOConnection1: TADOConnection;
    ADOQuery1: TADOQuery;
    DataSource1: TDataSource;
    DBGrid1: TDBGrid;
    Edit1: TEdit;
    Edit2: TEdit;
    Label1: TLabel;
    Label2: TLabel;
    ComboBox1: TComboBox;
    Label3: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure FormShow(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  Edit1.Clear;
  Edit2.Clear;
  With ADOQuery1 do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select * from tb_bookcount where bookname = :name');
    Parameters.ParamByName('name').Value := ComboBox1.Text;
    Open;
  end;
  if ADOQuery1.RecordCount>0 then
  begin
    if ADOQuery1.FieldByName('num').Value<0 then
      Edit1.Text := FloatToStr(Abs(ADOQuery1.FieldByName('num').Value))
    else
      Edit2.Text := FloatToStr(ADOQuery1.FieldByName('num').Value);
  end;
end;

procedure TForm1.FormShow(Sender: TObject);
var
  i : Integer;
begin
  With ADOQuery1 do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select bookname from tb_bookcount');
    Open;
  end;
  ADOQuery1.First;
  for i:=1 to ADOQuery1.RecordCount do
  begin
    ComboBox1.Items.Add(ADOQuery1.FieldByName('bookname').AsString);
    ADOQuery1.Next;
  end;
  ADOQuery1.Close;
end;

end.