登陆方式设计

1.

program Project1;

uses
  Vcl.Forms,
  Unit1 in 'Unit1.pas' {Form1},
  Unit2 in 'Unit2.pas' {Form2};

{$R *.res}

begin
  Application.Initialize;
  Application.MainFormOnTaskbar := True;
  if Login() then
    Application.CreateForm(TForm1, Form1);
  Form1.Caption := '登录成功';
  Application.Run;
end.

2.

unit Unit2;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type
  TForm2 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
function Login():Boolean; //方法声明
var
  Form2: TForm2;

implementation
uses Unit1;
{$R *.dfm}

function  Login():Boolean; //方法定义
var
  FormLogin:TForm2;
begin
//  FormLogin:=TForm2.Create(nil);
  Application.CreateForm(TForm2, FormLogin);
//  FormLogin:=TForm2.Create(Application);
  Result := FormLogin.ShowModal = mrOk;
  FormLogin.Free;
end;

procedure TForm2.Button1Click(Sender: TObject);
begin
  ModalResult:=mrOK;
end;

end.

3.

unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Vcl.ExtCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    Panel1: TPanel;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation
uses Unit2;
{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  Caption :=
  Application.MainForm.Name;
end;

end.