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ERC1155 what is the bytes data parameter?

I'm trying to create an ERC-1155 token and I'm using the method _mintBatch

https://docs.openzeppelin.com/contracts/3.x/api/token/erc1155#ERC1155-_mintBatch-address-uint256---uint256---bytes-

_mintBatch(address to, uint256[] ids, uint256[] amounts, bytes data)

and it has a parameter

bytes data that I have no idea what it's used for

enter image description here

It doesn't say what I need to use there in the documentation

What am I supposed to fill in for that parameter?

Solution

  • Well, I've always just passed 0x or "" in the data parameter and everything works fine. As for the contract why it has the data parameter, it doesn’t use the data parameter but passes it on. If you needed to pass additional data for mint and transfers then you could use data.

    if you go down into the rabbit hole in the git repo, You can see in the last of the _batchmint function that _afterTokenTransfer is called. It is used in nearly all other major functions. It is called solidity hooks. maybe you want to emit a separate event in the hook for the data or something. It really depends.

    You can read more about hooks here in the oppenzepplin docs.