I'm trying to deploy the following smart contract:

pragma solidity ^0.5.00;

contract TestContract {

   address public owner;
   string public word;

   constructor(string memory _word) public{
      owner = msg.sender;
      word = _word;

   modifier onlyOwner() {
      require(msg.sender == owner);

   function getWord() public view returns (string memory) {

   function updateWord(string memory _word) public onlyOwner {
      word = _word;

But I'm having trouble deploying it with the constructors parameters. I'm using MetaMask and web3.js (that I got from here: https://github.com/ethereum/web3.js/blob/develop/dist/web3.js) with the following test code:

var Web3 = require('web3');
var web3 = new Web3(web3.currentProvider);

var code = '0x608060405234801561001057600080fd5b506040516106b...';

var abi = JSON.parse('[{"constant":true,"inputs":[],"name":"word","outputs":...');

var myContract;
function createExampleContract() {

    document.getElementById('create').style.visibility = 'hidden';
    document.getElementById('code').innerText = code;

    web3.eth.defaultAccount = web3.eth.coinbase;
    document.getElementById('status').innerText = "transaction sent, waiting for confirmation";

    web3.eth.contract(abi).new({data: code}, function (err, contract) {
        if(err) {
        } else if(contract.address){
            myContract = contract;
            console.log('address: ' + myContract.address);
            document.getElementById('status').innerText = 'Mined!';
            document.getElementById('call').style.visibility = 'visible';

function callExampleContract() {
    var param = parseInt(document.getElementById('value').value);

    myContract.getWord(param, function(err, result) {
      if (err) {
        console.log('e: ' + err);
      } else {
        console.log('r: ' + result);

I got the code and abi with this two terminal commands solc --bin contract.sol and solc --abi contract.sol

I was trying arguments:['param'] after data:code and the contract deployment goes through but when I call the getWord method, this error shows up BigNumber Error: new BigNumber() not a base 16 number and searching on-line I found out that this may accour due to null values returning from the method call. So how do I deploy the contract with constructor arguments properly?

Thank you all!! =)

2 Answers 2


Looking at the web3 v0.20.xx documentation, the constructor parameters go just before the {data:code} like this:

web3.eth.contract(abi).new(param1,param2,{data:code}, callback);

Hope this helps for future references!


Referncing the documentation: web3.js v1.3.1
solc version: 0.8.0
web3.js version: 1.3.1

Suppose following is your smart contract:

contract myContract{
    constructor(int a, string memory str){
        // Some code using the arguments.

Following is how you deploy the contract:

var intObj = 10;
var strObj = 'Hello';
contract = await new web3.eth.Contract(compiledContract.abi)
        data: compiledContract.bytecode, 
        arguments: [intObj, strObj] // Writing you arguments in the array
    .send({ from: accounts[0], gas: minGas });

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