import "@thirdweb-dev/contracts/extension/PlatformFee.sol";

PlatformFee allows you to charge a percentage fee wherever there is a transfer of currency (ERC20 tokens or native tokens) in your contract.

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The PlatformFee extension is an abstract contract, and expects you to implement the following functions by yourself:

This is an example smart contract demonstrating how to inherit from this extension and override the functions to add (optional) custom functionality.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@thirdweb-dev/contracts/extension/PlatformFee.sol";
contract MyContract is PlatformFee {
    /**
     *  We store the contract deployer's address only for the purposes of the example
     *  in the code comment below.
     *
     *  Doing this is not necessary to use the `PlatformFee` extension.
     */
    address public deployer;
    constructor() {
        deployer = msg.sender;
    }
    /**
     *  This function returns who is authorized to set platform fee info for your contract.
     *
     *  As an EXAMPLE, we'll only allow the contract deployer to set the platform fee info.
     *
     *  You MUST complete the body of this function to use the `PlatformFee` extension.
     */
    function _canSetPlatformFeeInfo() internal view virtual override returns (bool) {
        return msg.sender == deployer;
    }
}

None of the base contracts implement this extension.