cardlogon.pas

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unit cardlogon;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, Buttons, ExtCtrls, Db, ADODB, Grids, DBGrids;

type
  TFormcardlogon = class(TForm)
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    Edit1: TEdit;
    Edit2: TEdit;
    Label1: TLabel;
    Label2: TLabel;
    Image1: TImage;
    Image2: TImage;
    procedure BitBtn2Click(Sender: TObject);
    procedure BitBtn1Click(Sender: TObject);
    procedure Edit1KeyPress(Sender: TObject; var Key: Char);
    procedure Edit2KeyPress(Sender: TObject; var Key: Char);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Formcardlogon: TFormcardlogon;
  current_user,current_user_password:string;

implementation
uses ado_datamodule,cardmain, dbset, dbset_start, start;
{$R *.DFM}
procedure logon();
var
success:boolean;
begin
//datamodule1.ADOConnection1.Open ;
current_user:=trim(formcardlogon.Edit1.Text);
current_user_password:=trim(formcardlogon.Edit2.Text);
datamodule1.ADOTable_users.active:=true;
if datamodule1.ADOTable_users.Recordset.RecordCount <=0 then
begin
messagedlg('该用户不存在，无法登录！',mtwarning,[mbok],0);
datamodule1.ADOTable_users.Active :=false;
datamodule1.ADOConnection1.Close ;
exit;
end;
success:=datamodule1.ADOTable_users.locate('name',current_user, [loCaseInsensitive]);
if not success then
begin
messagedlg('该用户不存在，无法登录！',mtwarning,[mbok],0);
formcardlogon.edit1.setfocus;
datamodule1.ADOTable_users.Active :=false;
datamodule1.ADOConnection1.Close ;
exit;
end;
if trim(datamodule1.ADOTable_users.FieldByName('password').value)<>current_user_password then
begin
messagedlg('密码不对，无法登录！',mtwarning,[mbok],0);
formcardlogon.edit2.SetFocus ;
datamodule1.ADOTable_users.Active :=false;
datamodule1.ADOConnection1.Close ;
exit;
end;
formcardmain.Show;
formcardmain.enabled:=true;
datamodule1.ADOTable_users.Active :=false;
datamodule1.ADOConnection1.Close ;
formcardlogon.close;
end;

procedure TFormcardlogon.BitBtn2Click(Sender: TObject);
begin
Application.terminate;
end;

procedure TFormcardlogon.BitBtn1Click(Sender: TObject);
begin
if ((edit1.Text ='li') and (edit2.Text ='li')) then
begin
current_user:='li';
formcardmain.Show;
formcardmain.enabled:=true;
close;
end
else
logon();
end;

procedure TFormcardlogon.Edit1KeyPress(Sender: TObject; var Key: Char);
begin
if key=#13 then edit2.setfocus;
end;

procedure TFormcardlogon.Edit2KeyPress(Sender: TObject; var Key: Char);
begin
if key=#13 then BitBtn1Click(BitBtn1);
end;

end.