private static PSBT BuildPsbt(Network network, HDFingerprint fingerprint, ExtPubKey xpub, KeyPath xpubKeyPath)
{
var deriveSendFromKeyPath = new KeyPath("1/0");
var deriveSendToKeyPath = new KeyPath("0/0");
KeyPath sendFromKeyPath = xpubKeyPath.Derive(deriveSendFromKeyPath);
KeyPath sendToKeyPath = xpubKeyPath.Derive(deriveSendToKeyPath);
PubKey sendFromPubKey = xpub.Derive(deriveSendFromKeyPath).PubKey;
PubKey sendToPubKey = xpub.Derive(deriveSendToKeyPath).PubKey;
BitcoinAddress sendFromAddress = sendFromPubKey.GetAddress(ScriptPubKeyType.Segwit, network);
BitcoinAddress sendToAddress = sendToPubKey.GetAddress(ScriptPubKeyType.Segwit, network);
TransactionBuilder builder = network.CreateTransactionBuilder();
builder = builder.AddCoins(new Coin(uint256.One, 0, Money.Coins(1), sendFromAddress.ScriptPubKey));
builder.Send(sendToAddress.ScriptPubKey, Money.Coins(0.99999m));
PSBT psbt = builder
.SendFees(Money.Coins(0.00001m))
.BuildPSBT(false);
var rootKeyPath1 = new RootedKeyPath(fingerprint, sendFromKeyPath);
var rootKeyPath2 = new RootedKeyPath(fingerprint, sendToKeyPath);
psbt.AddKeyPath(sendFromPubKey, rootKeyPath1, sendFromAddress.ScriptPubKey);
psbt.AddKeyPath(sendToPubKey, rootKeyPath2, sendToAddress.ScriptPubKey);
return(psbt);
}