我想在这种情况下处理这种情况，用户在这台机器上执行购买，但在另一台机器上运行该功能。
我知道我必须检查收据。我想知道，这是正确的方法吗？请注意，我绕过签名检查。因为，我需要设置一个我现在不想考虑的后端系统。我什至无法在本地执行签名检查，因为 Windows 8 Store App 不提供 System.Security.Cryptography API。
我想知道，以下代码片段是否足以处理大多数情况？请注意，我无法测试代码，因为我需要发布新版本才能测试代码。
private async void history_Click(object sender, RoutedEventArgs e)
{
bool OK = true;
// The next line is commented out for production/release.
LicenseInformation licenseInformation = CurrentApp.LicenseInformation;
if (!licenseInformation.ProductLicenses["PremiumFeatures"].IsActive)
{
try
{
// The customer doesn't own this feature, so
// show the purchase dialog.
String receipt = await CurrentApp.RequestProductPurchaseAsync("PremiumFeatures", true);
// the in-app purchase was successful
licenseInformation = CurrentApp.LicenseInformation;
if (licenseInformation.ProductLicenses["PremiumFeatures"].IsActive || receipt.Length > 0)
{
// In some situations, you may need to verify that a user made an in-app purchase.
// For example, imagine a game that offers downloaded content. If the user who
// purchased the content wants to play the game on another PC, you need to verify
// that the user purchased the content.
//
// Receipt is used to handle such situation.
//
// Validate receipt is complicated, as it requires us to setup a backend system.
// http://msdn.microsoft.com/en-US/library/windows/apps/jj649137
//
// I will just assume non empty receipt string means valid receipt.
OK = true;
}
else
{
OK = false;
}
}
catch (Exception)
{
// The in-app purchase was not completed because
// an error occurred.
OK = false;
}
}
else
{
// The customer already owns this feature.
OK = true;
}
if (OK)
{
// Launch premium feature.
Frame.Navigate(typeof(HistoryPage));
}
}