从 UA 判断是否为 Windows 平台
获取 UA:window.navigator.userAgent
window.navigator.userAgent
$t.REGEXP_IS_WINDOWS.test('Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.116 Safari/537.36') // true