Deploy contract with Ether

Question

I need to deploy a contract within Solidity while also sending Ether to it.

To deploy a contract I do

contract NewContract {
  constructor() public payable {
    // I need to receive Ether here
  }  
}

contract Deployer {
  function deploy() {
    address nc = new NewContract();
  }
}

How can I also send some Ether while deploying? In the same transaction?

You may want to check https://ethereum.stackexchange.com/questions/15953/send-ethers-from-one-contract-to-another to see if it provides any info — R.D, Sep 20 '18 at 09:13
Thanks but those answers suggest creating another function that receives ether. I've improved my question and it's more explicit where I need to receive the Ether now — Daniel Luca CleanUnicorn, Sep 20 '18 at 09:17

libertylocked · Accepted Answer · 2018-09-20T09:29:29.093

2

There are certainly cases where you want to feed contract ether in constructor only. In that case you can use .value to send some ether while constructing the contract.

contract A {
    function deployB() public payable returns (address) {
        B instance = (new B).value(msg.value)(42); // deploy B with `msg.value` wei, and put `42` as argument in constructor
        return instance;
    }
}

contract B {
    uint public num;
    constructor(uint _num) public payable {
        require(msg.value > 0); // value gets transferred from A when A deploys it
        num = _num; // num gets set to 42 when A deploys it
    }
}

edited Sep 20 '18 at 09:29

answered Sep 20 '18 at 09:26

libertylocked

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I understand that the value sent is msg.value but what does (42) represent in your example? – Daniel Luca CleanUnicorn Sep 20 '18 at 09:28
It's the constructor argument in B – libertylocked Sep 20 '18 at 09:28

Deploy contract with Ether

1 Answers1