11-2-ABI解码-decode

ABI Decode

abi.encode将数据编码为bytes. abi.decode解码bytes回数据。

而ABI解码有1个函数：abi.decode，用于解码abi.encode的数据

abi.encode encodes data into bytes. abi.decode decodes bytes back into data.

abi.decode用于解码abi.encode生成的二进制编码，将它还原成原本的参数。

我们将abi.encode的二进制编码输入给decode，将解码出原来的参数。

function decode(bytes memory data) public pure returns(uint dx, address daddr, string memory dname, uint[2] memory darray) {
    (dx, daddr, dname, darray) = abi.decode(data, (uint, address, string, uint[2]));
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

contract AbiDecode {
    struct MyStruct {
        string name;
        uint[2] nums;
    }

    function encode(
        uint x,
        address addr,
        uint[] calldata arr,
        MyStruct calldata myStruct
    ) external pure returns (bytes memory) {
        return abi.encode(x, addr, arr, myStruct);
    }

    function decode(
        bytes calldata data
    )
        external
        pure
        returns (uint x, address addr, uint[] memory arr, MyStruct memory myStruct)
    {
        // (uint x, address addr, uint[] memory arr, MyStruct myStruct) = ...
        (x, addr, arr, myStruct) = abi.decode(data, (uint, address, uint[], MyStruct));
    }
}