function bid(uint256 _userCode, uint256 _amount) public {
        assert(_userCode> 0);
        assert(_amount> 0);

        winningBid.userCode= _userCode;
        winningBid.amount= _amount;

        var bidData= Bid(_userCode, _amount);
        bids.push(bidData);
    }

var result = bidFunction.SendTransactionAndWaitForReceiptAsync(address, gas, balance, null, userCode, amount).Result;