Ethereum Cookbook

Interface contracts

1. Create an interface contract using the interface keyword:

interface InterfaceContract {    // ...}

2. Interface contracts are similar to abstract contracts, but they cannot have any implemented functions:

interface ERC20 {    function transfer(        address target,         uint amount) public;    function transferFrom(        address source,        address target,        uint amount) public;    ...}

3. Interfaces cannot inherit other contracts or interfaces, but can be inherited by other contracts:

interface ERC20 {    function transfer(address target, uint amount) public;}contract Token is ERC20 {    function transfer(address target, uint amount) public {        //...    }}

4. Interface contracts are limited to what the Contract ABI can represent. Use this to create a contract ...