The document discusses the ERC-1155 token standard which allows for both fungible and non-fungible tokens to be transferred together in a single transaction, providing benefits over existing standards like ERC-20 and ERC-721. It provides an overview of the standard's functions and events as well as examples of how it can be implemented using OpenZeppelin's ERC-1155 contract. The presentation also covers how to publish an ERC-1155 based NFT collection on the OpenSea marketplace.

1. INSTANTLY
TRADEABLE NFT
CONTRACTS BASED
ON ERC-1155
STANDARD
NFT Contracts, Presentation Part Ⅲ
12/2/2021

2. DISCLAIMER
§ The views and opinions expressed by the Presenter are those of the Presenter.
§ Presentation is not intended as legal or financial advice and may not be used as legal or
financial advice.
§ Every effort has been made to assure this information is up-to-date as of the date of
publication.

3. POPULAR PROJECTS

4. PRIMARY MARKET SALES IN USD

5. TERMINOLOGY: FUNGIBLE AND NON-
FUNGIBLE ASSETS
Fungible Non-fungible

6. WHY YET ANOTHER TOKEN
STANDARD?
BENEFITS ERC-1155
Effective transfer for massive amount of tokens
Multiple tokens combined in single contract
Safe transfer due to check for validity of destination transfer

7. COMBINED BENEFITS OF FUNGIBLE
AND NON-FUNGIBLE TOKENS
Games have specific needs to represent assets
Same tokens can be used in multiple games
ERC -1155 token
x1000
x2

8. MULTIPLE TOKENS SWAPPED
TOGETHER
ERC -1155 token #1
x100
0
x
2
ERC -1155 token #2
x1
x
3
x200
0

9. ENJIN EXPLANATION OF BATCH
OPERATIONS
ERC-20
ERC-1155

10. CODE VIEW: EXAMPLE OF ERC-1155
TOKEN

11. FUNCTIONS
balanceOf(account, id)
balanceOfBatch(accounts, ids)
setApprovalForAll(operator, approved)
isApprovedForAll(account, operator)
safeTransferFrom(from, to, id, amount, data)
safeBatchTransferFrom(from, to, ids, amounts,
data)
IERC165
supportsInterface(interfaceId)

12. EVENTS
TransferSingle(operator, from, to, id,
value)
TransferBatch(operator, from, to, ids,
values)
ApprovalForAll(account, operator,
approved)
URI(value, id)

13. ERC-721 VS ERC-1155
Feature ERC-721 ERC-1155
Fungibility Non-fungible Fungible and Non-fungible
Multiple tokens
transfer in the
same transaction
Only one at a time Multiple tokens transfer option
Smart Contract
reusability
One smart contract per token
type
Different types can use the
same contract
Localization Limited to one language Unicode support
Events On transfer and approave Mint, burn, transfer, approve

14. OPEN ZEPPELIN 1155 CONTRACT
WIZZARD

15. MINTABLE, BURNABLE, PAUSABLE
[1/3]
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.2;
import "@openzeppelin/contracts/token/ERC1155/ERC1155.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/Pausable.sol";
import "@openzeppelin/contracts/token/ERC1155/extensions/ERC1155Burnable.sol";
import "@openzeppelin/contracts/token/ERC1155/extensions/ERC1155Supply.sol";
contract MeetupToken is ERC1155, Ownable, Pausable, ERC1155Burnable, ERC1155Supply {
constructor() ERC1155("") {}
function setURI(string memory newuri) public onlyOwner {
_setURI(newuri);
}
function pause() public onlyOwner {
_pause();
}
…

16. MINTABLE, BURNABLE, PAUSABLE
[2/3]
…
function unpause() public onlyOwner {
_unpause();
}
function mint(address account, uint256 id, uint256 amount, bytes memory data)
public
onlyOwner
{
_mint(account, id, amount, data);
}
function mintBatch(address to, uint256[] memory ids, uint256[] memory amounts, bytes memory
data)
public
onlyOwner
{
_mintBatch(to, ids, amounts, data);
}
…

17. MINTABLE, BURNABLE, PAUSABLE
[3/3]
…
function _beforeTokenTransfer(address operator, address from, address to, uint256[] memory ids,
uint256[] memory amounts, bytes memory data)
internal
whenNotPaused
override(ERC1155, ERC1155Supply)
{
super._beforeTokenTransfer(operator, from, to, ids, amounts, data);
}
}

18. PUBLISH COLLECTION ON
OPENSEA

19. PUBLISH COLLECTION ON
OPENSEA (STEP 1)

20. PUBLISH COLLECTION ON
OPENSEA (STEP 2)

21. ABOUT PRESENTER
Gene Leybzon
https://www.linkedin.com/in/leybzon/
https://www.meetup.com/members/
9074420/
https://www.leybzon.com