Swift - 通过url地址打开web页面

let urlString = "http://hangge.com"
if let url = URL(string: urlString) {
    //根据iOS系统版本，分别处理
    if #available(iOS 10, *) {
        UIApplication.shared.open(url, options: [:],
                                  completionHandler: {
                                    (success) in
        })
    } else {
        UIApplication.shared.openURL(url)
    }
}