VIP181 non-fungible token¶

Overview¶

The VIP-181 Standard outlines a set of common methods that all NFT tokens can follow on the VeChainThor Network to transfer tokens, as well as allow tokens to be approved so they can be spent by another on-chain third party safely.

Specification¶

Methods¶

name¶

function name() public view returns(string)

Gets the name of the token.

Return: the name of the token

symbol¶

function symbol() public view returns(string)

Gets the symbol of the token.

Return: the symbol of the token

totalSupply¶

function totalSupply() public view returns(uint256)

Gets the total token supply.

Return: the total token supply

balanceOf¶

function balanceOf(address _owner) public view returns(uint256)

Gets the amount of NTFs the _owner possesses.

Params:

_owner: the address of owner

Return: the balance of owner

ownerOf¶

function ownerOf(uint256 _tokenId) public view returns(address)

Gets the owner of _tokenId.

Params:

_tokenId: the token id

Return: the owner address

transferFrom¶

function transferFrom(address _from, address _to, uint256 _tokenId) public

Transfer ownership of an NFT from address _from to address _to, and MUST emit the Transfer event. The function MUST throw if the transaction failed.

Params:

_from: the payment address
_to: the receiver address
_tokenId: the token id

approve¶

function approve(address _spender, uint256 _tokenId) public

Allows _spender to control your token with _tokenId, and MUST emit the Approval event. If this function is called again it overwrites the current allowance with _tokenId.

Params:

_spender: the spender address
_tokenId: the token id

getApproved¶

function getApproved(uint256 _tokenId) public view returns(address)

Get the approved address for _tokenId

Return: the approved address

setApprovalForAll¶

function setApprovalForAll(address _operator, bool _approved) public

Enable or disable approval for _operator address to manage all your assets, and MUST emit the ApprovalForAll event.

Params:

_operator: the approved address
_approved: True if the operator is approved, false to revoke approval

isApprovedForAll¶

function isApprovedForAll(address _owner, address _operator) public view returns(bool)

Check if an address is an authorized operator for another address

Params:

_owner: the address of owner
_operator: the address that acts on behalf of the owner

Return: the result of authorization

Events¶

Transfer¶

event Transfer(address indexed _from, address indexed _to, uint256 indexed _tokenId)

MUST trigger when the following scenario occurs:

when transferring tokens
when minting tokens
when burning tokens

Approval¶

event Approval(address indexed _owner, address indexed _spender, uint256 indexed _tokenId)

MUST trigger when call the approve method successfully.

ApprovalForAll¶

event ApprovalForAll(address indexed _owner, address indexed _operator, bool _approved)

MUST trigger when call the setApprovalForAll method successfully.