In App Purchases

[damichab]

I have written an app for the Microsoft Store. While I can see if license has been purchased or if still running under a trial period, I cannot for the life of me get the in-app purchase to work. I have followed various examples from both MS websites and elsewhere.

private void testButton_Click(object sender, EventArgs e)
{
_ = SetStore();
}



[ComImport]
[Guid("4AEEEC08-7C92-4456-A0D6-1B675C7AC005")]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
private interface IInitializeWithWindow
{
void Initialize(IntPtr hwnd);
}

private async Task SetStore()
{
try
{
StoreContext theStore = StoreContext.GetDefault();

// "Unable to cast object of type 'Windows.Services.Store.StoreContext' to type 'IInitializeWithWindow'."
// IInitializeWithWindow initWindow = (IInitializeWithWindow)(object)theStore;
// initWindow.Initialize(System.Diagnostics.Process.GetCurrentProcess().MainWindowHandle);

StoreProductResult app = await theStore.GetStoreProductForCurrentAppAsync();

// This works...
StoreProduct product = app.Product;
string title = product.Title;
string price = product.Price.FormattedPrice;

// This works...
StoreAppLicense license = await theStore.GetAppLicenseAsync();
bool trial = license.IsTrial;
bool full = license.IsActive;



// "Invalid window handle.\r\n\r\nThis function must be called from a UI thread"
//StorePurchaseResult result = await theStore.RequestPurchaseAsync("9NRFBVGVGW8K");

// "Invalid window handle.\r\n\r\nThis function must be called from a UI thread"
// Windows.Foundation.IAsyncOperation<StorePurchaseResult> purchase = product.RequestPurchaseAsync();


}
catch (Exception e)
{
int a = 1;
}

}





The app is written in .NET with a UWP wrapper to create the MSIX package. The rem'ed lines indicate where I am having issues. Can anyone help me with these?


Otherwise, do I have to offer in app purchase for a trial program or can I just direct the user back to the Microsoft Store when they are ready to buy? As stated above, the code that checks for a valid license is working well.

Continue reading...