unit1.pas

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unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ComCtrls, ExtCtrls, StdCtrls, DB, ADODB;

type
  TLoginForm = class(TForm)
    StatusBar1: TStatusBar;
    PageControl1: TPageControl;
    TabSheet1: TTabSheet;
    Panel1: TPanel;
    Label3: TLabel;
    Label2: TLabel;
    PassWord: TEdit;
    login1: TButton;
    exit1: TButton;
    TabSheet2: TTabSheet;
    Panel2: TPanel;
    Label4: TLabel;
    Label5: TLabel;
    Label7: TLabel;
    password2: TEdit;
    login2: TButton;
    exit2: TButton;
    TabSheet3: TTabSheet;
    Label8: TLabel;
    Label10: TLabel;
    password3: TEdit;
    login3: TButton;
    exit3: TButton;
    TabSheet4: TTabSheet;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    procedure login1Click(Sender: TObject);
    procedure PassWordKeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure usernameKeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure exit1Click(Sender: TObject);
   // procedure FormCreate(Sender: TObject);
    procedure login2Click(Sender: TObject);
    procedure login3Click(Sender: TObject);
    procedure password2KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure password3KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure eixt4Click(Sender: TObject);

    procedure username4KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure Button1Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }     
  public
     
    { Public declarations }
  end;

var
  LoginForm: TLoginForm;
  user:string;
implementation

uses Unit2, Unit5, StudentInfoUnit, GradeUnit, Unit8, Unit9;

{$R *.dfm}

procedure TLoginForm.login1Click(Sender: TObject);
var sqlstr:string;
begin
 //if UserName.Text=''
   //then messagedlg(#10'请输入用户名.', mtwarning,[mbOk],0)            //用户名为空
 if PassWord.Text=''  then
   messagedlg(#10'请输入密码.', mtwarning,[mbOk],0)       //密码为空
     else if PassWord.Text='520' then
       begin                                          //验证用户名/密码
          Application.CreateForm(TMainForm, MainForm);
          LoginForm.hide;
          MainForm.show;
       end;


end;

procedure TLoginForm.PassWordKeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);                           //密码框内按回车,调用loginClick事件
begin
  if key=13 then  login1Click(sender);               
end;

procedure TLoginForm.usernameKeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);                             //用户名框内按回车,模拟Tab键
begin
  if key=13 then PostMessage(LoginForm.Handle,WM_KEYDOWN,VK_TAB,0);
end;

procedure TLoginForm.exit1Click(Sender: TObject); // 程序退出
begin
     application.Terminate;
end;




procedure TLoginForm.login2Click(Sender: TObject);
begin
 //if UserName2.Text=''
   //then messagedlg(#10'请输入用户名.', mtwarning,[mbOk],0)            //用户名为空
 if PassWord2.Text=''
          then messagedlg(#10'请输入密码.', mtwarning,[mbOk],0)
        else  if PassWord2.Text='520'      //密码为空

             then  begin
                            Application.CreateForm(TManageForm, ManageForm);
                            LoginForm.hide;
                            ManageForm.show;

           end
end;

procedure TLoginForm.login3Click(Sender: TObject);
begin
 //if UserName3.Text=''
  // then messagedlg(#10'请输入用户名.', mtwarning,[mbOk],0)            //用户名为空
   if PassWord3.Text=''
          then messagedlg(#10'请输入密码.', mtwarning,[mbOk],0)       //密码为空
          else
                 if PassWord3.Text='520'
               then  begin
                            Application.CreateForm(TStudentInfoForm, StudentInfoForm);
                            LoginForm.hide;
                            StudentInfoForm.show;
                           end
end;           

procedure TLoginForm.password2KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
 if key=13 then  login2Click(sender);
end;

procedure TLoginForm.password3KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
 if key=13 then  login3Click(sender);
end;

procedure TLoginForm.eixt4Click(Sender: TObject);
begin
  application.Terminate;
end;


procedure TLoginForm.username4KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
if key=13 then PostMessage(LoginForm.Handle,WM_KEYDOWN,VK_TAB,0);
end;



procedure TLoginForm.Button1Click(Sender: TObject);
begin
form8.show();
end;

procedure TLoginForm.Button3Click(Sender: TObject);
begin
Form9.show();
end;

end

.