go调用solidity 合约新方法

上周在群聊吹牛，吹吹我写的golang 调用solana合约的东西。有人说他要学习go调用solidity的方法。我看了看我在登链的无abi调用合约的方法，写的python的，ethers的，solidity的，就是没写golang的，确实可以写写。

那个群里人都说用chatgpt都会用abigen的方式生成go包的方式调用合约方法。 所以我讲种不需要使用abigen生成go包的方法调用合约。

我还是喜欢使用我的晓道fork版，https://github.com/daog1/ethgo fork自，umbracle/ethgo 好处我不讲，自己读代码。

合约调用最早都是需要abi文件生成的方式，后面还是有了更简单方式，最早我是ethers里面看到叫

A Human-Readable ABI

ethers是这么写的：

// A Human-Readable ABI; for interacting with the contract, we
// must include any fragment we wish to use
const abi = [
    // Read-Only Functions
    "function balanceOf(address owner) view returns (uint256)",
    "function decimals() view returns (uint8)",
    "function symbol() view returns (string)",

    // Authenticated Functions
    "function transfer(address to, uint amount) returns (bool)",

    // Events
    "event Transfer(address indexed from, address indexed to, uint amount)"
];

// This can be an address or an ENS name
const address = "0x70ff5c5B1Ad0533eAA5489e0D5Ea01485d530674";

// Read-Only; By connecting to a Provider, allows:
// - Any constant function
// - Querying Filters
// - Populating Unsigned Transactions for non-constant methods
// - Estimating Gas for non-constant (as an anonymous sender)
// - Static Calling non-constant methods (as anonymous sender)
const erc20 = new ethers.Contract(address, abi, provider);

// Read-Write; By connecting to a Signer, allows:
// - Everything from Read-Only (except as Signer, not anonymous)
// - Sending transactions for non-constant functions
const erc20_rw = new ethers.Contract(address, abi, signer);

ethgo 有点fork ethers的意思，所以也支持Human-Readable ABI 的方式。 代码这么写

package main

import (
    "fmt"
    "math/big"

    "github.com/umbracle/ethgo"
    "github.com/umbracle/ethgo/abi"
    "github.com/umbracle/ethgo/contract"
    "github.com/umbracle/ethgo/jsonrpc"
)

func handleErr(err error) {
    if err != nil {
        panic(err)
    }
}

func main() {
    var functions = []string{
        "function totalSupply() view returns (uint256)",  //Human-Readable ABI 
    }

    abiContract, err := abi.NewABIFromList(functions)
    handleErr(err)

    // Matic token
    addr := ethgo.HexToAddress("0x7d1afa7b718fb893db30a3abc0cfc608aacfebb0") 

    client, err := jsonrpc.NewClient("https://eth.llamarpc.com")
    handleErr(err)

    c := contract.NewContract(addr, abiContract, contract.WithJsonRPC(client.Eth()))
    res, err := c.Call("totalSupply", ethgo.Latest)  //call totalSupply
    handleErr(err)

    fmt.Printf("TotalSupply: %s", res["0"].(*big.Int))
}

原版代码在这里：https://github.com/daog1/ethgo/blob/main/examples/contract-call-basic.go 我的那个fork 版，如果你发现什么问题，可以跟我说。 我一般都用Human-Readable ABI 的方式调用，abigen这种太麻烦了，容易搞错。