private void FetchTransactionPosition(byte[] txHash, bool requireConfirmed, Action <ErrorCode, UInt64, UInt64> handler) { var managedHash = new hash_t { hash = txHash }; IntPtr contextPtr = CreateContext(handler, managedHash); ChainNative.chain_fetch_transaction_position(nativeInstance_, contextPtr, managedHash, requireConfirmed ? 1 : 0, internalFetchTransactionPositionHandler_); }