导航跳转

https://hovertree.com/h/bjag/px54lgkm.htm

https://blog.csdn.net/weixin_50900104/article/details/127075385

//xaml.cs
private void address(object sender, EventArgs e)
    {
        //跳转官网
        Uri uri = new Uri("https://www.baidu.com/");
         Browser.Default.OpenAsync(uri, BrowserLaunchMode.SystemPreferred);
    }

主页面替换（特别登录到主页面）

 Application.Current.MainPage = new AppShell();

导航跳转

https://www.cnblogs.com/functionMC/p/17016494.html

https://www.cnblogs.com/functionMC/p/17016612.html