这里主要学习这个类：

OSVERSIONINFO

 

unit Unit1;
interface
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;
type
  TForm1 = class(TForm)
    Button1: TButton;
    Memo1: TMemo;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
var
  Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
var
  osinfo:OSVERSIONINFO;
begin
  osinfo.dwOSVersionInfoSize:=sizeof(OSVERSIONINFO);
//通过API函数获得版本信息
  GetVersionEx(osinfo);
//在MEMO中显示信息
  Memo1.Lines.Append('当前操作系统的主版本号为：'
        +IntToStr(osinfo.dwMajorVersion));
  Memo1.Lines.Append('当前操作系统的次版本号为：'
    +IntToStr(osinfo.dwMinorVersion));
  Memo1.Lines.Append('当前操作系统的构件数为：'
    +IntToStr(osinfo.dwBuildNumber));
  Memo1.Lines.Append('当前操作系统的平台为：'
    +IntToStr(osinfo.dwPlatformId));
  Memo1.Lines.Append('当前操作系统的补丁号为：'
    +osinfo.szCSDVersion);
end;

end.

源码下载：http://bbs.txwb.com/read-htm-tid-249057.html