谁帮忙翻译下这段delphi的话，没一句或块 是什么一是 加个备注或解释一下关键函数就行

[helei1026]

unit Login;

interface

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

type
TFrmLogin = class(TForm)
Panel1: TPanel;
Label2: TLabel;
Label3: TLabel;
EdName: TEdit;
EdPwd: TEdit;
SbtCancle: TSpeedButton;
SbtOk: TSpeedButton;
procedure SbtCancleClick(Sender: TObject);
procedure SbtOkClick(Sender: TObject);
procedure FormActivate(Sender: TObject);
procedure EdPwdKeyPress(Sender: TObject; var Key: Char);
procedure EdNameKeyPress(Sender: TObject; var Key: Char);
private
{ Private declarations }
public
{ Public declarations }
IsValid: Boolean;
CurrUser:String;
end;

var
FrmLogin: TFrmLogin;

implementation

uses Enrollment;

{$R *.dfm}

procedure TFrmLogin.SbtCancleClick(Sender: TObject);
begin
Self.Close;
end;

procedure TFrmLogin.SbtOkClick(Sender: TObject);
var
users:TUsers;
begin
try
users :=TUsers.Create(self);
IsValid :=users.LoginIsValid(EdName.Text,EdPwd.Text);
if IsValid then
begin
self.Close;
CurrUser :=EdName.Text ;
end else
begin
MessageDlg(users.ErrPrompt ,mtError, [mbYes], 0);
EdPwd.Text :='';
EdName.SelectAll;
EdName.SetFocus;
end;
finally
users.Free;
end;
end;

procedure TFrmLogin.FormActivate(Sender: TObject);
begin
IsValid :=False;
CurrUser :='';
EdName.SetFocus;
end;

procedure TFrmLogin.EdPwdKeyPress(Sender: TObject; var Key: Char);
begin
if key=#13 then SbtOk.Click;
end;

procedure TFrmLogin.EdNameKeyPress(Sender: TObject; var Key: Char);
begin
if key=#13 then
if EdName.Text ='' then
begin
MessageDlg('用户名不能为空，请重新输入',mtError, [mbYes], 0);
EdName.SelectAll;
EdName.SetFocus
end else
EdPwd.SetFocus;
end;

end.

[bdmh]

unit Login; 

interface 

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

type 
TFrmLogin = class(TForm) 
Panel1: TPanel; 
Label2: TLabel; 
Label3: TLabel; 
EdName: TEdit; 
EdPwd: TEdit; 
SbtCancle: TSpeedButton; 
SbtOk: TSpeedButton; 
procedure SbtCancleClick(Sender: TObject); 
procedure SbtOkClick(Sender: TObject); 
procedure FormActivate(Sender: TObject); 
procedure EdPwdKeyPress(Sender: TObject; var Key: Char); 
procedure EdNameKeyPress(Sender: TObject; var Key: Char); 
private 
{ Private declarations } 
public 
{ Public declarations } 
IsValid: Boolean; 
CurrUser:String; 
end; 

var 
FrmLogin: TFrmLogin; 

implementation 

uses Enrollment; 

{$R *.dfm} 

procedure TFrmLogin.SbtCancleClick(Sender: TObject); 
begin 
Self.Close; 
end; 

procedure TFrmLogin.SbtOkClick(Sender: TObject); 
var 
users:TUsers; 
begin 
try 
users :=TUsers.Create(self); 
IsValid :=users.LoginIsValid(EdName.Text,EdPwd.Text); //判断用户是否有效
if IsValid then 
begin 
self.Close; 
CurrUser :=EdName.Text ; 
end else 
begin 
MessageDlg(users.ErrPrompt ,mtError, [mbYes], 0); 
EdPwd.Text :=''; 
EdName.SelectAll; 
EdName.SetFocus; 
end; 
finally 
users.Free; 
end; 
end; 

procedure TFrmLogin.FormActivate(Sender: TObject); 
begin 
IsValid :=False; 
CurrUser :=''; 
EdName.SetFocus; 
end; 

procedure TFrmLogin.EdPwdKeyPress(Sender: TObject; var Key: Char); 
begin 
if key=#13 then SbtOk.Click; 
end; 

procedure TFrmLogin.EdNameKeyPress(Sender: TObject; var Key: Char); //按键事件
begin 
if key=#13 then //回车
if EdName.Text ='' then 
begin 
MessageDlg('用户名不能为空，请重新输入',mtError, [mbYes], 0); 
EdName.SelectAll; 
EdName.SetFocus 
end else 
EdPwd.SetFocus; 
end; 

end.