// 初始化CurrentAppSimulator
var file = await Package.Current.InstalledLocation.GetFileAsync("Data\\license.xml");
await Windows.ApplicationModel.Store.CurrentAppSimulator.ReloadSimulatorAsync(file); 

C#

using Windows.ApplicationModel.Store;
using Windows.Foundation;namespace ContosoCookbook
{class AppLicenseDataSource : INotifyPropertyChanged{public event PropertyChangedEventHandler PropertyChanged;private bool _licensed = false;private string _price;public AppLicenseDataSource(){if (CurrentAppSimulator.LicenseInformation.IsTrial){CurrentAppSimulator.LicenseInformation.LicenseChanged += OnLicenseChanged;GetListingInformationAsync();}else_licensed = true;}private async void GetListingInformationAsync(){var listing = await CurrentAppSimulator.LoadListingInformationAsync();_price = listing.FormattedPrice;}private void OnLicenseChanged(){if (!CurrentAppSimulator.LicenseInformation.IsTrial){_licensed = true;CurrentAppSimulator.LicenseInformation.LicenseChanged -= OnLicenseChanged;((ContosoCookbook.App)App.Current).Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>{if (PropertyChanged != null){PropertyChanged(this, new PropertyChangedEventArgs("IsLicensed"));PropertyChanged(this, new PropertyChangedEventArgs("IsTrial"));PropertyChanged(this, new PropertyChangedEventArgs("LicenseInfo"));}});}}public bool IsLicensed{get { return _licensed; }}public bool IsTrial{get { return !_licensed; }}public string LicenseInfo{get{if (!_licensed)return "Trial Version";elsereturn ("Valid until " + CurrentAppSimulator.LicenseInformation.ExpirationDate.LocalDateTime.ToString("dddd, MMMM d, yyyy"));}}public string FormattedPrice{get{if (!String.IsNullOrEmpty(_price))return "Upgrade to the Full Version for " + _price;elsereturn "Upgrade to the Full Version";}}}
}
}

注意：您刚添加的AppLicenseDataSource类实现了INotifyPropertyChanged接口并公开了名称为IsLicensed, IsTrial, LicenseInfo和 FormattedPrice的属性。前面两个使用CurrentAppSimulator.LicenseInformation.IsTrial来确定现在运行的应用程序是否已经购买或以试用版运行。如果应用程序是试用版，LicenseInfo返回“Trial Version”字符串，或者如果不是试用版，返回包含许可证的过期日期的字符串。FormattedPrice返回一个包含应用程序价格的按钮标签，该价格从Windows应用商店获得(或者在这里来自WindowsStoreProxy.xml)。价格信息来自通过CurrentAppSimulator.LoadListingInformationAsync 检索获得的ListingInformation对象。

XAML

<UserControlx:Class="ContosoCookbook.AboutUserControl"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:local="using:ContosoCookbook"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:common="using:ContosoCookbook.Common"mc:Ignorable="d"d:DesignHeight="300"d:DesignWidth="400">

XAML

<UserControl.Resources><local:AppLicenseDataSource x:Key="License" /><common:BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
</UserControl.Resources>

注意：BooleanToVisibilityConverter是一个简单的值转换器，它将布尔值true转换为Visibility.Visible，将false转换为Visibility.Collapsed。它在Visual Studio创建项目时已经被包含在其中。

XAML

<TextBlock Text="{Binding LicenseInfo, Source={StaticResource License}}" FontFamily="Segoe UI" FontWeight="SemiLight" FontSize="18" TextWrapping="Wrap" />
<Button x:Name="PurchaseButton" Width="225" Height="120" Margin="0,24,0,0" Visibility="{Binding IsTrial, Source={StaticResource License}, Converter={StaticResource BooleanToVisibilityConverter }}"><Button.Content><TextBlock Text="{Binding FormattedPrice, Source={StaticResource License}}" TextWrapping="Wrap" TextAlignment="Center" /></Button.Content>
</Button>

</Button>

练习 2: 模拟应用购买

XAML

Click="OnPurchaseButtonClicked"

3、打开AboutUserControl.xaml.cs并添加以下using语句。

using Windows.ApplicationModel.Store;

4、然后添加以下事件处理程序。

private void OnPurchaseButtonClicked(object sender, RoutedEventArgs e)
{// 购买应用程序CurrentAppSimulator.RequestAppPurchaseAsync(false);
}

5、在测试许可证之前，我们需要缓存App对象的调度程序(dispatcher)，因为LicenseChanged事件可以在后台线程中触发，并且我们在事件中使用数据绑定来更新用户界面。打开App.xaml.cs并向App类添加以下成员和属性。

        Windows.UI.Core.CoreDispatcher _dispatcher = null; public Windows.UI.Core.CoreDispatcher Dispatcher{get{return _dispatcher;} }

protected override void OnWindowCreated(WindowCreatedEventArgs args){_dispatcher = args.Window.Dispatcher; base.OnWindowCreated(args);}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Windows.ApplicationModel.Store;namespace ContosoCookbook
{class ProductLicenseDataSource : INotifyPropertyChanged{public event PropertyChangedEventHandler PropertyChanged;private const string _name = "ItalianRecipes";private bool _licensed = false;private string _price;public string GroupTitle{set{if (value != "Italian")_licensed = true;else if (CurrentAppSimulator.LicenseInformation.ProductLicenses[_name].IsActive)_licensed = true;else{CurrentAppSimulator.LicenseInformation.LicenseChanged += OnLicenseChanged;GetListingInformationAsync();}}}private async void GetListingInformationAsync(){var listing = await CurrentAppSimulator.LoadListingInformationAsync();_price = listing.ProductListings[_name].FormattedPrice;}private void OnLicenseChanged(){if (CurrentAppSimulator.LicenseInformation.ProductLicenses[_name].IsActive){_licensed = true;CurrentAppSimulator.LicenseInformation.LicenseChanged -= OnLicenseChanged;((ContosoCookbook.App)App.Current).Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{if (PropertyChanged != null){PropertyChanged(this, new PropertyChangedEventArgs("IsLicensed"));PropertyChanged(this, new PropertyChangedEventArgs("IsTrial"));}
});             }}public bool IsLicensed{get { return _licensed; }}public bool IsTrial{get { return !_licensed; }}public string FormattedPrice{get{if (!String.IsNullOrEmpty(_price))return "Purchase Italian Recipes for " + _price;elsereturn "Purchase Italian Recipes";}}}
}

<local:ProductLicenseDataSource x:Key="License" />
<common:BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>

<TextBlock FontSize="20" FontWeight="Light" Text="{Binding Directions}" TextWrapping="Wrap" Visibility="{Binding IsLicensed, Source={StaticResource License}, Converter={StaticResource BooleanToVisibilityConverter }}" />
<Button Width="225" Height="120" Background="#30ffffff" Click="OnPurchaseProduct" Visibility="{Binding IsTrial, Source={StaticResource License}, Converter={StaticResource BooleanToVisibilityConverter }}"><Button.Content><TextBlock Text="{Binding FormattedPrice, Source={StaticResource License}}" TextWrapping="Wrap" TextAlignment="Center" /></Button.Content>
</Button>

5、打开ItemDetailPage.xaml.cs并在文件顶部添加以下using语句。

using Windows.ApplicationModel.Store;

6、在LoadState方法的结束处添加以下语句。

// 将组标题传递给LicenseDataSource (重要!)
ProductLicenseDataSource license = (ProductLicenseDataSource)this.Resources["License"];
license.GroupTitle = item.Group.Title;

C#

private void OnPurchaseProduct(object sender, RoutedEventArgs e)
{// 首先检查是否是试用版，您不能在试用版购买产品 if (CurrentAppSimulator.LicenseInformation.IsTrial)new Windows.UI.Popups.MessageDialog("Please go into About page in Settings and license first", "You must upgrade from trial first").ShowAsync(); else{// 购买意大利食谱产品 CurrentAppSimulator.RequestProductPurchaseAsync("ItalianRecipes", false);
}
}

任务 2 – 进行产品购买

现在所有剩下的工作就是测试您的修改并观察产品购买的运行。

1、按F5启动应用程序。

2、点击某个意大利食谱以转到项-明细页面。

3、确认购买按钮出现在烹饪指南处，如图3所示。

图 3 产品购买用户界面

4、点击按钮以启动产品购买。

5、在Windows应用商店对话框中点击Continue以模拟产品购买。

6、确认按钮消失并且烹饪指南出现在它的位置。

7、查看一些其他的意大利食谱并验证烹饪指南按预期方式显示。

8、返回Visual Studio并停止调试。

您在本实验中进行的练习演示了一些Windows应用商店API最重要的方面：如何检测试用版，如何模拟应用程序购买，如何模拟应用内的产品购买以及如何检索有关这些产品的信息。当然在实际的应用程序中，您将以CurrentApp调用替换CurrentAppSimulator调用。这样您将具备通过应用程序盈利的所有工具。请继续前行并创造收益！

祝您在Windows 8中编程快乐！