V2Router02

V2Router02 is used as a intermediate contract to interact with liquidity pools, or the lower level V2Pair contract. The contract can be used to swap, add liquidity, withdraw liquidity. The contract also contains many variations of these three tasks that can be used for each unique situation like using native gas tokens (i.e. ETH), and Fee-On-Transfer tokens with a tax when transfers happen.

The full contract can be found here.

Read-Only Functions

factory

function factory() external pure returns (address);

Returns factory address.

WETH

function WETH() external pure returns (address);

Returns the canonical WETH address on the Ethereum mainnet, or the canonical native wrapped address for the network the contracts are deployed on.

quote

See quote.

getAmountOut

See getAmountOut.

getAmountIn

See getAmountIn.

getAmountsOut

function getAmountsOut(uint amountIn, address[] memory path) public view returns (uint[] memory amounts);

See getAmountsOut.

getAmountsIn

function getAmountsIn(uint amountOut, address[] memory path) public view returns (uint[] memory amounts);

See getAmountsIn.

State-Changing Functions

addLiquidity

function addLiquidity(
  address tokenA,
  address tokenB,
  uint amountADesired,
  uint amountBDesired,
  uint amountAMin,
  uint amountBMin,
  address to,
  uint deadline
) external returns (uint amountA, uint amountB, uint liquidity);

Adds liquidity to an ERC-20⇄ERC-20 pool.

  • To cover all possible scenarios, msg.sender should have already given the router an allowance of at least amountADesired/amountBDesired on tokenA/tokenB.

  • Always adds assets at the ideal ratio, according to the price when the transaction is executed.

  • If a pool for the passed tokens does not exists, one is created automatically, and exactly amountADesired/amountBDesired tokens are added.

  • amountAMin and amountBMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

addLiquidityETH

function addLiquidityETH(
  address token,
  uint amountTokenDesired,
  uint amountTokenMin,
  uint amountETHMin,
  address to,
  uint deadline
) external payable returns (uint amountToken, uint amountETH, uint liquidity);

Adds liquidity to an ERC-20⇄WETH pool with ETH.

  • To cover all possible scenarios, msg.sender should have already given the router an allowance of at least amountTokenDesired on token.

  • Always adds assets at the ideal ratio, according to the price when the transaction is executed.

  • msg.value is treated as a amountETHDesired.

  • Leftover ETH, if any, is returned to msg.sender.

  • If a pool for the passed token and WETH does not exists, one is created automatically, and exactly amountTokenDesired/msg.value tokens are added.

  • amountTokenMin and amountETHMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

removeLiquidity

function removeLiquidity(
  address tokenA,
  address tokenB,
  uint liquidity,
  uint amountAMin,
  uint amountBMin,
  address to,
  uint deadline
) external returns (uint amountA, uint amountB);

Removes liquidity from an ERC-20⇄ERC-20 pool.

  • msg.sender should have already given the router an allowance of at least liquidity on the pool.

  • amountAMin and amountBMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

removeLiquidityETH

function removeLiquidityETH(
  address token,
  uint liquidity,
  uint amountTokenMin,
  uint amountETHMin,
  address to,
  uint deadline
) external returns (uint amountToken, uint amountETH);

Removes liquidity from an ERC-20⇄WETH pool and receive ETH.

  • msg.sender should have already given the router an allowance of at least liquidity on the pool.

  • amountTokenMin and amountETHMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

removeLiquidityWithPermit

function removeLiquidityWithPermit(
  address tokenA,
  address tokenB,
  uint liquidity,
  uint amountAMin,
  uint amountBMin,
  address to,
  uint deadline,
  bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountA, uint amountB);

Removes liquidity from an ERC-20⇄ERC-20 pool without pre-approval.

  • amountAMin and amountBMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

removeLiquidityETHWithPermit

function removeLiquidityETHWithPermit(
  address token,
  uint liquidity,
  uint amountTokenMin,
  uint amountETHMin,
  address to,
  uint deadline,
  bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountToken, uint amountETH);

Removes liquidity from an ERC-20⇄WETTH pool and receive ETH without pre-approval.

  • amountAMin and amountBMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

removeLiquidityETHSupportingFeeOnTransferTokens

function removeLiquidityETHSupportingFeeOnTransferTokens(
  address token,
  uint liquidity,
  uint amountTokenMin,
  uint amountETHMin,
  address to,
  uint deadline
) external returns (uint amountETH);

Identical to removeLiquidityETH, but succeeds for tokens that take a fee on transfer.

Parameters

Returns

removeLiquidityETHWithPermitSupportingFeeOnTransferTokens

function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
  address token,
  uint liquidity,
  uint amountTokenMin,
  uint amountETHMin,
  address to,
  uint deadline,
  bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountETH);

Identical to removeLiquidityETHWithPermit, but succeeds for tokens that take a fee on transfer.

Parameters

Returns

swapExactTokensForTokens

function swapExactTokensForTokens(
  uint amountIn,
  uint amountOutMin,
  address[] calldata path,
  address to,
  uint deadline
) external returns (uint[] memory amounts);

Swaps an exact amount of input tokens for as many output tokens as possible, along the route determined by the path. The first element of path is the input token, the last is the output token, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).

  • path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.

  • msg.sender should have already given the router an allowance of at least amountIn on the input token.

  • amountOutMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

swapTokensForExactTokens

function swapTokensForExactTokens(
  uint amountOut,
  uint amountInMax,
  address[] calldata path,
  address to,
  uint deadline
) external returns (uint[] memory amounts);

Receive an exact amount of output tokens for as few input tokens as possible, along the route determined by the path. The first element of path is the input token, the last is the output token, and any intermediate elements represent intermediate tokens to trade through (if, for example, a direct pair does not exist).

  • path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.

  • msg.sender should have already given the router an allowance of at least amountIn on the input token.

  • amountInMax can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

swapExactETHForTokens

function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
  external
  payable
  returns (uint[] memory amounts);

Swaps an exact amount of ETH for as many output tokens as possible, along the route determined by the path. The first element of path must be WETH, the last is the output token, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).

  • path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.

  • amountOutMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

swapTokensForExactETH

function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
  external
  returns (uint[] memory amounts);

Receive an exact amount of ETH for as few input tokens as possible, along the route determined by the path. The first element of path is the input token, the last must be WETH, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).

  • msg.sender should have already given the router an allowance of at least amountInMax on the input token.

  • If the to address is a smart contract, it must have the ability to receive ETH.

  • path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.

  • amountInMax can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

swapExactTokensForETH

function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
  external
  returns (uint[] memory amounts);

Swaps an exact amount of tokens for as much ETH as possible, along the route determined by the path. The first element of path is the input token, the last must be WETH, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).

  • If the to address is a smart contract, it must have the ability to receive ETH.

  • path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.

  • amountOutMin can be used for slippage protection.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

swapETHForExactTokens

function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
  external
  payable
  returns (uint[] memory amounts);

Receive an exact amount of tokens for as little ETH as possible, along the route determined by the path. The first element of path must be WETH, the last is the output token and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).

  • Leftover ETH, if any, is returned to msg.sender.

  • path.length must be >= 2. Pools for each consecutive pair of addresses must exist and have liquidity.

  • deadline is used to set a time restriction on how long it can take for the tx to be executed.

Parameters

Returns

swapExactTokensForTokensSupportingFeeOnTransferTokens

function swapExactTokensForTokensSupportingFeeOnTransferTokens(
  uint amountIn,
  uint amountOutMin,
  address[] calldata path,
  address to,
  uint deadline
) external;

Identical to swapExactTokensForTokens, but succeeds for tokens that take a fee on transfer.

  • msg.sender should have already given the router an allowance of at least amountIn on the input token.

Parameters

swapExactETHForTokensSupportingFeeOnTransferTokens

function swapExactETHForTokensSupportingFeeOnTransferTokens(
  uint amountOutMin,
  address[] calldata path,
  address to,
  uint deadline
) external payable;

Identical to swapExactETHForTokens, but succeeds for tokens that take a fee on transfer.

Parameters

swapExactTokensForETHSupportingFeeOnTransferTokens

function swapExactTokensForETHSupportingFeeOnTransferTokens(
  uint amountIn,
  uint amountOutMin,
  address[] calldata path,
  address to,
  uint deadline
) external;

Identical to swapExactTokensForETH, but succeeds for tokens that take a fee on transfer.

  • If the to address is a smart contract, it must have the ability to receive ETH.

Parameters

Interface

pragma solidity >=0.6.2;

import './IUniswapV2Router01.sol';

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

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