1.保存到Applicaion Data配置信息中：
保存：
private void testTB_TextChanged(object sender, TextChangedEventArgs e){ ApplicationDataContainer localSettings = ApplicationData.Current.LocalSettings; localSettings.Values["value"] = testTB.Text;}
读取：
private void NavigationHelper_LoadState(object sender, LoadStateEventArgs e){ ApplicationDataContainer localSettings = ApplicationData.Current.LocalSettings; if (localSettings.Values.ContainsKey("value")) { testTB.Text = localSettings.Values["value"].ToString(); }}
2.放到页面状态中保存
保存：
private void NavigationHelper_SaveState(object sender, SaveStateEventArgs e){ e.PageState["value"] = testTB.Text;}
读取：
private void NavigationHelper_LoadState(object sender, LoadStateEventArgs e){ if (e.PageState != null && e.PageState.ContainsKey("value")) { testTB.Text = e.PageState["value"].ToString(); }}