unit Login;

interface

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

type
  TfrmLogin = class(TForm)
    Image1: TImage;
    Label1: TLabel;
    edtUserId: TEdit;
    edtPassword: TEdit;
    bbtnOK: TBitBtn;
    bbtnCancle: TBitBtn;
    Label2: TLabel;
    procedure bbtnOKClick(Sender: TObject);
    procedure bbtnCancleClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  frmLogin: TfrmLogin;
function gfunOpenLogin(var sUserID :string; nStatus :integer) :integer;
implementation
uses DataModual,SportMain;
var
  usUserID :string;   //接收用戶標識
  unStatus :integer;  //與nStatus含義一樣
  unTimes  :integer;  // 計算用戶登錄次數
{$R *.dfm}
//登錄表單提供出來的接口函數
function gfunOpenLogin(var sUserID :string; nStatus :integer) :integer;
begin
   frmLogin :=TfrmLogin.Create(nil);    //動態創建登錄表單對象
   unStatus :=nStatus;                  //將調用者參數送入unStatus變量中
   unTimes  :=1;                        //初始登錄數字設為1
   frmLogin.ShowModal;                  //顯示登錄界面
   sUserID :=usUserID;                  //將登錄界面的用戶標識返回給調用者
   Result :=0;                          //函數返回0值
   frmLogin.Free;                       //釋放登錄表單對象
end;
procedure TfrmLogin.bbtnOKClick(Sender: TObject);
var
   sPassword :string;
   sConn :string;
begin
   sPassword :=trim(edtPassword.Text);
   usUserID :=trim(edtUserID.Text);
   if usUserID = '' then
   begin
     application.MessageBox('沒有輸入用戶標識','提示',mb_ok) ;
      edtUserID.SetFocus ;
      exit;
   end;
   sConn := 'Provider=OraOLEDB.Oracle.1;Password='+sPassword+
       '; Persist Security Info=True;User ID='+usUserID+';Data Source=demo';
   if DataModule1.connOracle.Connected then
      DataModule1.connOracle.Close;
   DataModule1.connOracle.ConnectionString := sConn;
   DataModule1.connOracle.LoginPrompt := False;
   try
      DataModule1.connOracle.Open;          //建立數據庫的連接
      close;                                //關閉登錄界面
      SportMain.frmSportMain.Show ;   //顯示主界面
   except
      application.MessageBox('輸入用戶標識或口令有錯','提示',mb_ok);
      unTimes := unTimes+1;
      if unTimes >3 then
      begin
        application.MessageBox('您已經試圖登錄三次不成功，退出系統','提示',mb_ok);
        application.Terminate ;
      end
      else
        edtUserID.SetFocus ;
   end;
end;

//取消登錄系統
procedure TfrmLogin.bbtnCancleClick(Sender: TObject);
begin
   if unStatus = 0 then    //初次取消退出整個應用程序
   begin
     if DataModule1.connOracle.Connected then
        DataModule1.connOracle.Close;
     application.Terminate ;
   end
   else                  //重新登錄后取消本次登錄
     close;
end;

end.