Bitcoin Forum

Hi,
I am creating an online wallet & I am using C# (WebAPI) as my backed scripting language.
I am also using NBitcoin & QBitninja NuGet packages developed by NicolasDorier.
Some how I created a verified transaction but network is not able to broadcast that transaction.

Command:- bitcoin-cli signrawtransaction 010000000001012be
973e52a7f8efbc91ef9c397a81df05c047e8138c76920fd9225df19aaea360000000000ffffffff 0
2a4c0e400000000001976a9140ecd86fcda32df67e7cbd989eddd38d00bb2504f88ac40420f0000 0
000001976a9145da61fbc2b8de68bbe1b666b4e84bec9d2e3edae88ac02473044022061199488e5 a
5fe9c3db4678eadc08b92de1d0881dd13ac3af5b39b15543ae4c202205ff7aeead9ba8c3f4bc89a c
0614802ae19f781be8bfa8c74fb01bd50b96c7cf4012103e970de664249bb560ec1501ea8a98571 d
a983c899ee02888d6e41aaab2ff56b300000000


 Err. :-  
{
  "hex": "010000000001012be973e52a7f8efbc91ef9c397a81df05c047e8138c76920fd9225df
19aaea360000000000ffffffff02a4c0e400000000001976a9140ecd86fcda32df67e7cbd989edd d
38d00bb2504f88ac40420f00000000001976a9145da61fbc2b8de68bbe1b666b4e84bec9d2e3eda e
88ac02473044022061199488e5a5fe9c3db4678eadc08b92de1d0881dd13ac3af5b39b15543ae4c 2
02205ff7aeead9ba8c3f4bc89ac0614802ae19f781be8bfa8c74fb01bd50b96c7cf4012103e970d e
664249bb560ec1501ea8a98571da983c899ee02888d6e41aaab2ff56b300000000",
  "complete": false,
  "errors": [
    {
      "txid": "36eaaa19df2592fd2069c738817e045cf01da897c3f91ec9fb8e7f2ae573e92b"
,
      "vout": 0,
      "scriptSig": "",
      "sequence": 4294967295,
      "error": "Input not found or already spent"
    }
  ]
}


Demo Code :-

public string SendBitCoins(int userId, int walletID, string destinationAddress, decimal amount)
        {
            try
            {
                var masterKey = new GetMasterWallet(userId);
                var privateKey = masterKey.PrivateKey;
                Money fee = Money.Satoshis(8476);
                Money transactionAmount = Money.Satoshis(Convert.ToInt64(amount * 100000000));
                var transaction = CreateTransaction(userId, walletID, privateKey.PubKey,transactionAmount,fee, masterKey);
                var transactionhex = BuildTransaction(transaction,privateKey, destinationAddress, amount, fee);
                return transactionhex;
            }
            catch (Exception)
            {

                throw;
            }
        }


public Transaction CreateTransaction(int userID,int userWalletID, PubKey sourcePublicKey, Money amount, Money fee, ExtKey masterwallet)
        {
            try
            {
                var init = new Transaction();
                if (userWalletID != 0)
                {
                    var client = new QBitNinjaClient(Network.TestNet);
                    var totalAmount = amount + fee;
                    long transactionAmount = 0;
                    var userRequestAddress = _unitOfWork.UserRequestAddressRepository
                        .GetManyQueryable(x => x.UserID == userID &&
                        x.UserWalletID == userWalletID && x.Amount > 0 && !x.IsActive);
                    var userPrivateWalletKey = new UserWalletChainService(_unitOfWork).GetUserWalletKey(userWalletID, masterwallet);
                    var userPublicWalletKey = userPrivateWalletKey.Neuter();
                    

                    userRequestAddress.ToList().ForEach(x => {
                        var extPubKey = userPublicWalletKey.Derive(
                                        new KeyPath(Convert.ToString(x.ChainDerivationKey)));
                        //var extPrivateKey = userPrivateWalletKey.Derive(
                        //                new KeyPath(Convert.ToString(x.ChainDerivationKey)));
                        client.GetBalance(extPubKey.PubKey.Hash.GetAddress(Network.TestNet), true)
                        .Result.Operations.ToList().ForEach(z => {
                            z.ReceivedCoins.ForEach(l => {
                                if (totalAmount.Satoshi > transactionAmount)
                                    //init.Outputs.Add(new TxOut(Money.Coins(1m), GetP2WPKH(sourcePublicKey)));
                                    init.Outputs.Add(new TxOut(Money.Coins(Convert.ToDecimal((l.Amount as Money).Satoshi) / 100000000), GetP2WPKH(sourcePublicKey)));
                                //init.Outputs.Add(new TxOut(Money.Coins(Convert.ToDecimal((l.Amount as Money).Satoshi) / 100000000), GetP2WPKH(userPrivateWalletKey.PrivateKey.PubKey)));

                                transactionAmount += (l.Amount as Money).Satoshi;
                            });
                        });
                    });
                }
                //init.Outputs.Add(new TxOut(Money.Coins(1m), GetP2WPKH(sourcePublicKey)));
                return init;
            }
            catch (Exception)
            {

                throw;
            }
        }


public string BuildTransaction(Transaction transaction, Key sourcePriveatKey, string destinationAddress,decimal amount,Money fee)
        {
            TransactionBuilder builder = null;
            try
            {
                var destination = BitcoinAddress.Create(destinationAddress).ScriptPubKey;
                

                Coin[] coins = transaction.Outputs.AsCoins().ToArray();
                
                builder = new TransactionBuilder();
                Transaction tx = builder
                    .AddCoins(coins[0])
                    .AddKeys(sourcePriveatKey)
                    .Send(destination, Money.Coins(amount))
                    .SetChange(sourcePriveatKey)
                    .SendFees(fee)
                    .BuildTransaction(sign: true);
                if (builder.Verify(tx))
                    return tx.ToHex();
                else
                    return "";
            }
            catch (Exception)
            {

                throw;
            }
        }


please give me some suggestion is anybody knows what I am doing wrong.

It appears that you're trying to send more Bitcoin than the address has, so the network is rejecting it. Make sure your units are correct in the amount you are sending.

Hi,
My units are same.
I think the transaction which I created is not correct, there is very limited help in this topic specifically in C#.
Do you have such kind of precooked code that will be more helpful.

Thanks :)

Your transaction is wrong! More precisely your Tx_in_count is 0 where it should be something bigger and equal to 1

01000000 00 01012be973e52a7f8efbc91ef9c397a81df05c....

The bold part is your VarInt which should indicate the number of Transaction Outputs you are spending. it shows 0 here. Possibly you are making a mistake in creating your VarInt since what comes next is not a valid tx id.
If you are spending 1 output, which I am guessing you are, it should simply be "01"

BTW Nbitcoin has a (near) live chat here: https://gitter.im/MetacoSA/NBitcoin