loginunit.pas

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unit LoginUnit;

interface

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

type
  TLoginForm = class(TForm)
    Image1: TImage;
    Label1: TLabel;
    Label2: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    procedure Edit1KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure Edit2KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure BitBtn2Click(Sender: TObject);
    procedure BitBtn1Click(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
  private
    { Private declarations }
    procedure WMNCpaint(var Msg:TWMNCPaint); message WM_NCPAINT;
  public
    { Public declarations }
  end;

var
  LoginForm: TLoginForm;

implementation
uses DMUnit,Share,MainUnit;

{$R *.dfm}

{ TLoginForm }

procedure TLoginForm.WMNCpaint(var Msg: TWMNCPaint);
begin
  inherited;
  Draw(LoginForm);
end;

procedure TLoginForm.Edit1KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
var
  dicr:boolean;
begin
    if (key=vk_down) or (key=13) then
      dicr:=True
    else if key=vk_up then
      dicr:=False
    else begin
      key:=0;
      exit;
    end;
    selectnext(activecontrol,dicr,true);
    if activecontrol is TEdit then
      (activecontrol as TEdit).SelectAll;
end;

procedure TLoginForm.Edit2KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
  if key=vk_up then
  begin
    key:=0;
    SelectNext(ActiveControl,False,True);
    if ActiveControl is TEdit then
      (ActiveControl as TEdit).SelectAll;
  end else
  if key=13 then
  begin
    key:=0;
    BitBtn1Click(sender);
  end else
  if key=vk_down then
  begin
    bitbtn1.SetFocus;
  end;
end;

procedure TLoginForm.BitBtn2Click(Sender: TObject);
begin
  Application.Terminate;
end;

procedure TLoginForm.BitBtn1Click(Sender: TObject);
begin
  if Edit1.Text='' then
  begin
    application.MessageBox('请输入用户名！','提示');
    edit1.SetFocus;
    exit;
  end else
  if Edit2.Text='' then
  begin
    application.MessageBox('请输入密码','提示');
    edit2.SetFocus;
    exit;
  end else
  if not DM.ValUserName(Trim(edit1.Text)) then
  begin
    application.MessageBox('无此用户名！请确认','提示');
    edit1.SetFocus;
    edit1.SelectAll;
    exit;
  end else
  if not DM.ValUser(Trim(edit1.Text),Trim(Edit2.Text)) then
  begin
    application.MessageBox('输入的密码错误！','提示');
    edit2.SetFocus;
    edit2.SelectAll;
    exit;
  end;
  curusername:=Trim(edit1.Text);
  SetMenu;//设置用户可用菜单
  DM.SaveLogIn(curusername);//写入用户登录日志
  MainForm.Caption:=application.Title+'-------当前用户：'+curusername;
  LoginForm.Close;
end;

procedure TLoginForm.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  if curusername='' then
    application.Terminate;
  LoginForm:=nil;
  Action:=CaFree;
end;

end.