Is it possible to achieve receive eth and mint nft in the same contract?

Question

recently I'm build some ERC721 nft contract.

I know that smart contract can receive ETH, so my question is that is it possible to write a payable function, and upon receive some ETH from someone, the contract will mint an NFT right away and send to the msg sender?

If not, what will be the recommended way to buy an NFT with ETH instead of going through some third party platform like OpenSea? Thanks!

Answer 1

yes indeed. Here's a small example of how we do it:

function mint(uint _parentTokenIndex) public payable 
{
    require(msg.value >= NFT_PRICE, "Not enough ETH sent.");
    require(!_assetExists[_parentTokenIndex], "The asset does not meet the unique constraint.");

    _mint(msg.sender, _id);
    _setTokenURI(_id, METADATA_URL);
    _assetExists[_parentTokenIndex] = true;
}

Steps are like this:

• Make your function payable.
• Add a requirement for sent eth: require(msg.value >= NFT_PRICE, "Not enough ETH sent.");.
• Mint your NFT.