TRC-20 - TRON Documentation

TRC‌-20 is a technical standard used for smart contracts on the TRON blockchain for implementing tokens with the TRON Virtual Machine (TVM). It is fully compatible to ERC‌-20.

Implementation Rules

3 Optional Items

• Token Name

string public constant name = “TRONEuropeRewardCoin”;

• Token Abbreviation

string public constant symbol = “TERC”;

• Token Precision

uint8 public constant decimals = 6;

6 Required Items

contract TRC20 {
    function totalSupply() constant returns (uint theTotalSupply);
    function balanceOf(address _owner) constant returns (uint balance);
    function transfer(address _to, uint _value) returns (bool success);
    function transferFrom(address _from, address _to, uint _value) returns (bool success);
    function approve(address _spender, uint _value) returns (bool success);
    function allowance(address _owner, address _spender) constant returns (uint remaining);
    event Transfer(address indexed _from, address indexed _to, uint _value);
    event Approval(address indexed _owner, address indexed _spender, uint _value);
}

• totalSupply()

This function returns the total supply of the token.

• balanceOf()

This function returns the token balance of the specific account.

• transfer()

This function is used to transfer an amount of tokens from the smart contract to a specific address.

• approve()

This function is used to authorize the third party (like a DAPP smart contract) to transfer token from the token owner’s account.

• transferFrom()

This function is used to allow the third party to transfer token from an owner account to a receiver account. The owner account must be approved to be called by the third party.

• allowance()

This function is used to query the remaining amount of tokens the third party can transfer.

2 Event Functions

When token is successfully transferred, it has to trigger Transfer Event.

When approval() is successfully called, it has to trigger Approval Event.

Example