unit1.pas

DELPHI7.0+SQL2005环境下开发 2008年8月假期所写

unit Unit1;
//login
interface

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

type
  Tfrm_login = class(TForm)
    Image1: TImage;
    Edit1: TEdit;
    Edit2: TEdit;
    SpeedButton1: TSpeedButton;
    SpeedButton2: TSpeedButton;
    procedure SpeedButton2Click(Sender: TObject);
    procedure SpeedButton1Click(Sender: TObject);
    procedure plogin;
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure Edit2KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  frm_login: Tfrm_login;
  m:integer = 0;
  s:boolean = False;
  yonghu: string;
implementation

uses Unit2, Unit13, Unit5;

{$R *.dfm}
//-------------------------退出-----------------------------//
procedure Tfrm_login.SpeedButton2Click(Sender: TObject);
begin
if s=false then
  application.Terminate
else
  close;
end;
//-------------------------登陆---------------------------//
procedure Tfrm_login.SpeedButton1Click(Sender: TObject);
begin
m := m+1; //记录输入字数，如果大于3次。则失败
if edit1.Text='' then
  application.MessageBox('请输入用户名','提示',64)
else
  if edit2.Text='' then
    application.MessageBox('请输入密码','提示',64)
  else
    plogin;
end;
//-----------------------登陆涵数-------------------//
procedure Tfrm_login.plogin;
begin
  with Data1.ADOlogin do
    begin
      close;
      sql.Clear;
      sql.Add('select * from admin where admin = :a and pass = :b');
      parameters.ParamByName('a').Value:=trim(edit1.Text);
      parameters.ParamByName('b').Value:=trim(edit2.Text);
      open;
    end;
  if Data1.ADOlogin.RecordCount>0 then
    begin
      yonghu := data1.ADOlogin.fieldByName('admin').Value;
      s := True;
      frm_main.StatusBar1.Panels[1].Text := yonghu;  //MAIN窗口中状态条设置显示用户名
      frm_main.StatusBar1.Panels[3].Text := datetostr(date());    //日期
      close;
    end
  else
    if m<3 then  //输入错误次数小于3
      begin
        application.MessageBox('用户名或密码错误，请重新输入','提示',64);
        edit1.Clear;
        edit2.Clear;
        edit1.SetFocus; //设焦点
      end
    else
      begin
        application.MessageBox('你无权使用本系统','提示',64);
        application.Terminate;
      end;
end;
//----------------------关闭--------------------------------//
procedure Tfrm_login.FormClose(Sender: TObject; var Action: TCloseAction);
begin
if s=false then
application.Terminate;
end;
//--------------------密码DEYDOWN事件------------------//
procedure Tfrm_login.Edit2KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
  if((Key = vk_Return) or (Key = vk_Down)) then
    SpeedButton1Click(sender)  //当按下回车或向下键时，执行登陆
  else
    Edit2.SetFocus;
  if Key = vk_Up then
    Edit1.SetFocus;  //使EDIT1焦点
end;

end.