IERC20Upgradeable.sol

View Source: @openzeppelin\contracts-upgradeable\token\ERC20\IERC20Upgradeable.sol

↘ Derived Contracts: ERC20Upgradeable, IERC20MetadataUpgradeable

IERC20Upgradeable

Interface of the ERC20 standard as defined in the EIP.

Events

event Transfer(address indexed from, address indexed to, uint256  value);
event Approval(address indexed owner, address indexed spender, uint256  value);

Functions

totalSupply

Returns the amount of tokens in existence.

function totalSupply() external view
returns(uint256)

Arguments

| Name | Type | Description | | ————- |————- | —–|

balanceOf

Returns the amount of tokens owned by account.

function balanceOf(address account) external view
returns(uint256)

Arguments

Name Type Description
account address  

transfer

Moves amount tokens from the caller’s account to to. Returns a boolean value indicating whether the operation succeeded. Emits a {Transfer} event.

function transfer(address to, uint256 amount) external nonpayable
returns(bool)

Arguments

Name Type Description
to address  
amount uint256  

allowance

Returns the remaining number of tokens that spender will be allowed to spend on behalf of owner through {transferFrom}. This is zero by default. This value changes when {approve} or {transferFrom} are called.

function allowance(address owner, address spender) external view
returns(uint256)

Arguments

Name Type Description
owner address  
spender address  

approve

Sets amount as the allowance of spender over the caller’s tokens. Returns a boolean value indicating whether the operation succeeded. IMPORTANT: Beware that changing an allowance with this method brings the risk that someone may use both the old and the new allowance by unfortunate transaction ordering. One possible solution to mitigate this race condition is to first reduce the spender’s allowance to 0 and set the desired value afterwards: https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729 Emits an {Approval} event.

function approve(address spender, uint256 amount) external nonpayable
returns(bool)

Arguments

Name Type Description
spender address  
amount uint256  

transferFrom

Moves amount tokens from from to to using the allowance mechanism. amount is then deducted from the caller’s allowance. Returns a boolean value indicating whether the operation succeeded. Emits a {Transfer} event.

function transferFrom(address from, address to, uint256 amount) external nonpayable
returns(bool)

Arguments

Name Type Description
from address  
to address  
amount uint256  

Contracts