Asynchronously saves changes to the wallet item. If this item is a Deal and the item is not in the Wallet, it will be added. If the item is a PaymentInstrument, WalletTransactionItem or an OnlinePaymentInstrument, you can only use this method to update the item if it already exists in the Wallet, otherwise an exception will be thrown. To add a new instance of PaymentInstrument or WalletTransactionItem, use the AddWalletItemTask. For more information, see How to use the add Wallet item task for Windows Phone 8.
Assembly: Microsoft.Phone (in Microsoft.Phone.dll)
The following table lists the fields that must be set before calling or using AddWalletItemTask. If these are not set, an InvalidOperationException will be thrown.