使用本地話的error
// 彈框網(wǎng)絡(luò)不行
let alert = UIAlertController(title: "??", message: err?.localizedDescription, preferredStyle: .alert)
alert.addAction(UIAlertAction(title: "ok", style: .default, handler: { (action:UIAlertAction) in
}))
self.present(alert, animated: true, completion: nil)
// 異步 到主線程
DispatchQueue.main.async {
}