login.pas

完整的delphi书籍源代码,大家有空的时候自己慢慢看看

unit Login;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Buttons, DBCtrls;

type
  TLoginFrm = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Edit1: TEdit;
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    DBComboBox1: TDBComboBox;
    procedure BitBtn1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    User:string;
    Login:boolean;
  end;

var
  LoginFrm: TLoginFrm;

implementation
   uses DataModule,Main;
{$R *.dfm}

procedure TLoginFrm.BitBtn1Click(Sender: TObject);
var
  s:string;
begin
  s:='Select * from Q_User where'+' User_ID='+DBComboBox1.Text+' and'+' User_Password'+'='+Edit1.text;
  with DM.AQ_User do
    begin
     close;
     SQl.Clear;
     SQL.Add('Select * from Q_User where'+' User_ID='+''''+DBComboBox1.Text+''''+' and'+' User_Password='+''''+Edit1.text+'''');
     open;
    end;
    if DM.AQ_User.RecordCount<1 then
      begin
       edit1.Text:='******';
       showmessage('密码不对！请联系管理员获取密码再登录！');
       DM.ADOConnection1.Connected:=false;
       Login:=false;
       LoginFrm.close;
      end
    else
      begin
       User:=DM.AQ_User.FieldValues['User_Name'];
       Login:=true;
       edit1.Text:='******';
       LoginFrm.close;
      end;
end;

procedure TLoginFrm.FormCreate(Sender: TObject);
begin
   Application.CreateForm(TDM,DM);
   DM.ADOConnection1.Connected:=true;
   DM.UserDS.Enabled:=true;
end;

procedure TLoginFrm.BitBtn2Click(Sender: TObject);
begin
   DM.ADOConnection1.Connected:=false;
   DM.UserDS.Enabled:=false;
   Login:=false;
   LoginFrm.close;
end;

end.