bitcoin block

var client = new QBitNinjaClient("http://api.qbit.ninja/", Network.Main);
var transactionId = uint256.Parse("sourceTransactionId");
var transactionResponse = client.GetTransaction(transactionId).Result;

Console.WriteLine(transactionResponse.TransactionId); //
Console.WriteLine(transactionResponse.Block.Confirmations);

BitcoinSecret sender = new BitcoinSecret("senderPrivateKey");
var receivedCoins = transactionResponse.ReceivedCoins;
OutPoint outPointToSpend = null;
foreach (var coin in receivedCoins)
{
    if (coin.TxOut.ScriptPubKey == sender.GetAddress(ScriptPubKeyType.Legacy).ScriptPubKey)
    {
        outPointToSpend = coin.Outpoint;
    }
}
if (outPointToSpend == null)
    throw new Exception("TxOut doesn't contain our ScriptPubKey");
Console.WriteLine("We want to spend {0}. outpoint:", outPointToSpend.N + 1);
var transaction = Transaction.Create(Network.Main);
transaction.Inputs.Add(new TxIn()
{
    PrevOut = outPointToSpend
});
var destinationAddress = new BitcoinPubKeyAddress("senderPublicKey", Network.Main);

var destinationAmount = new Money(0.001m, MoneyUnit.BTC);
var minerFee = new Money(0.0001m, MoneyUnit.BTC);
var txInAmount = (Money)receivedCoins[(int)outPointToSpend.N].Amount;
var changeAmount = txInAmount - destinationAmount - minerFee;
transaction.Outputs.Add(destinationAmount, destinationAddress.ScriptPubKey);
// Send the change back
transaction.Outputs.Add(changeAmount, sender.GetAddress(ScriptPubKeyType.Legacy).ScriptPubKey);
var message = "John's transaction is on the block";
var bytes = Encoding.UTF8.GetBytes(message);
transaction.Outputs.Add(Money.Zero, TxNullDataTemplate.Instance.GenerateScriptPubKey(bytes));
transaction.Inputs[0].ScriptSig = sender.GetAddress(ScriptPubKeyType.Legacy).ScriptPubKey;

BroadcastResponse broadcastResponse = client.Broadcast(transaction).Result;

if (!broadcastResponse.Success)
{
    Console.Error.WriteLine("ErrorCode: " + broadcastResponse.Error.ErrorCode);
    Console.Error.WriteLine("Error message: " + broadcastResponse.Error.Reason);
}
else
{
    Console.WriteLine("Success! You can check out the hash of the transaciton in any block explorer:");
    Console.WriteLine(transaction.GetHash());
}