wp7 页面导航传值和在Tombstoning之后保存状态保存状态

const string CurrentEntryDateKey = "CurrentEntryDateKey";

//If we return to this page after Tomstoning, then get the previous state from
            // PhoneApplicationService
            if (PhoneApplicationService.Current.State.ContainsKey(CurrentEntryDateKey))
                _entryDate = (DateTime)PhoneApplicationService.Current.State[CurrentEntryDateKey];

 在xaml中导航使用&时需要用转义字符，&amp;    如：<HyperlinkButton NavigateUri="/ChildPage/Video.xaml?param1=视频&amp;param2=参数2">

而在后台则不用

NavigationService.Navigate(new Uri("/ChildPage/Music.xaml?"+ "param1=" + TextBox1.Text + "&param2=" + TextBox2.Text , UriKind.Relative));