function InitializeSetup: Boolean;
var Path:string ;
    ResultCode: Integer;
begin
  if RegKeyExists(HKLM, 'SOFTWARE\Microsoft\.NETFramework\policy\v2.0') then
  begin
    Result := true;
  end
  else
  begin
    if MsgBox('系统检测到您没有安装.Net Framework2.0，是否立刻下载并安装？', mbConfirmation, MB_YESNO) = idYes then
    begin
      Path := ExpandConstant('{pf}\Internet Explorer\iexplore.exe');
      Exec(Path, 'http://www.xxx.com/down/dotnetfx2.exe', '', SW_SHOWNORMAL, ewWaitUntilTerminated, ResultCode);
      MsgBox('请安装好.Net Framework2.0环境后，再运行本安装包程序！',mbInformation,MB_OK);
      Result := false;
    end
    else
    begin
      MsgBox('没有安装.Net Framework2.0环境，无法运行XXX程序，本安装程序即将退出！',mbInformation,MB_OK);
      Result := false;
    end;
  end;
end;