LaunchSkype.cs

private async void Button_Click(object sender, RoutedEventArgs e)
{
        //直接開啟Skype
        await Launcher.LaunchUriAsync(new Uri("skype:"));

        //開啟Skype並撥打給user1
        //await Launcher.LaunchUriAsync(new Uri("skype:user1?call"));

        //開啟Skype並與user1聊天
        //await Launcher.LaunchUriAsync(new Uri("skype:user1?chat"));
}