BuildProofOfTumbleBitConceptTransactions

Program.cs

private static void BuildProofOfTumbleBitConceptTransactions()
{
	uint256 txIdToSpend = _qBitClient.GetBalance(_fundingAddress, unspentOnly: false).Result.Operations.First().TransactionId;
	Transaction txToSpend = _qBitClient.GetTransaction(txIdToSpend).Result.Transaction;

	var tOfferExtKey = _seed.ExtKey.Derive(1, false);
	var tOfferDestination = tOfferExtKey.ScriptPubKey.GetDestinationAddress(_network); // mk1soVb7Se1t99v7APGqiXofr2pKVS7hN5
	var tFulfillExtKey = _seed.ExtKey.Derive(2, false);
	var tFulfillDestination = tFulfillExtKey.ScriptPubKey.GetDestinationAddress(_network); // n4mey3skuXQna149vUaanuAPyEDiunsryT

	var fee = new Money(0.001m, MoneyUnit.BTC);
	var builder = new TransactionBuilder();
	var tOffer = builder
		.AddCoins(txToSpend)
		.AddKeys(_fundingExtKey)
		.SendFees(fee)
		.Send(tOfferDestination, txToSpend.Outputs.First().Value - fee)
		.BuildTransaction(sign: true);

	var errors = builder.Check(tOffer);
	if (errors.Count() != 0)
	{
		ReportErrors(txName: nameof(tOffer), errors: errors);
	}
	else
	{
		ReportTransaction(txName: nameof(tOffer), transaction: tOffer);
	}

	builder = new TransactionBuilder();
	var tFulfill = builder
		.AddCoins(tOffer)
		.AddKeys(tOfferExtKey)
		.SendFees(fee)
		.Send(tFulfillDestination, tOffer.Outputs.First().Value - fee)
		.BuildTransaction(sign: true);

	errors = builder.Check(tFulfill);
	if (errors.Count() != 0)
	{
		ReportErrors(txName: nameof(tFulfill), errors: errors);
	}
	else
	{
		ReportTransaction(txName: nameof(tFulfill), transaction: tOffer);
	}
}