SwapFactory Contract Guide: OKTC Documentation

Contract Overview

Contract Name: SwapFactory
Contract Address: 0x7b9F0a56cA7D20A44f603C03C6f45Db95b31e539
👉 View Contract on GitHub
👉 Track on OkLink Explorer

Core Functions

Read Functions

getHash()

function getHash() public pure returns(bytes32);

Returns the CreationCode of the SwapPair contract.

getPair(address tokenA, address tokenB)

function getPair(address tokenA, address tokenB) external view returns (address pair);

• Fetches the pair contract address for tokenA and tokenB.
• Order of tokens doesn’t matter.
• Returns a zero address if no pair exists.

allPairs(uint index)

function allPairs(uint) external view returns (address pair);

• Retrieves the address of the nth pair (0-indexed).
• Zero address indicates an uncreated pair.

allPairsLength()

function allPairsLength() external view returns (uint);

• Returns the total count of pairs created.

feeTo() and feeToSetter()

function feeTo() external view returns (address);
function feeToSetter() external view returns (address);

• feeTo: Address receiving protocol fees.
• feeToSetter: Address authorized to update feeTo.

Write Functions

createPair(address tokenA, address tokenB)

function createPair(address tokenA, address tokenB) external returns (address pair);

• Deploys a new pair for tokenA and tokenB.
• Emits a PairCreated event (see below).

setFeeTo(address _feeTo) and setFeeToSetter(address _feeToSetter)

• Admin functions to configure fee addresses.

Events

PairCreated

event PairCreated(address indexed token0, address indexed token1, address pair, uint);

• Triggered on new pair creation.
• token0 and token1 are sorted addresses.
• The uint value increments with each new pair (1, 2, etc.).

FAQ Section

1. What happens if I call getPair for non-existent tokens?

The function returns 0x0000000000000000000000000000000000000000.

2. How are tokens ordered in a pair?

Tokens are sorted alphabetically by address (e.g., token0 < token1).

3. Who can change the feeTo address?

Only the feeToSetter address has permission.

4. Can I create multiple pairs for the same tokens?

No, the factory enforces unique pairs per token combination.

5. Where can I verify the contract code?

👉 Check GitHub Repository

Best Practices

• Use allPairsLength to paginate through pairs.
• Always validate pair existence before interactions.
• Monitor PairCreated events for real-time pair deployments.

This guide adheres to OKTC’s latest standards (2024).