如何使用 web3.py 在給定的 ETH 地址獲取特定的代幣余額

Question

我開始使用 web.py。 我有一個要求，我需要在給定的 ETH 地址（該地址不是合同所有者）處獲取可用的令牌余額，通過我偶然發現以下功能的文檔：

https://web3py.readthedocs.io/en/stable/contracts.html#web3.contract.ContractFunction.call

token_contract.functions.myBalance().call({'from': web3.eth.accounts[1]})

所以在上面幾行，我寫了這個：

from web3 import HTTPProvider, Web3
import requests

w3 = Web3(HTTPProvider('https://ropsten.infura.io/RPw9nHRS7Ue47RaKVvHM'))

url_eth = "https://api.etherscan.io/api"
contract_address = '0x0CdCdA4E7FCDD461Ba82B61cBc4163E1022f22e4'
API_ENDPOINT = url_eth+"?module=contract&action=getabi&address="+str(contract_address)

r = requests.get(url = API_ENDPOINT)
response = r.json()

instance = w3.eth.contract(
    address=Web3.toChecksumAddress(contract_address),
    abi = response["result"]
)
send_address = "0xF35A192475527f80EfcfeE5040C8B5BBB596F69A"
balance = instance.functions.balance_of.call({'from':send_address}) 
#balnce = instance.functions.myBalance.call({'from':send_address})
print("----------------------",balance)

我收到以下錯誤：

"Are you sure you provided the correct contract abi?"
web3.exceptions.MismatchedABI: ("The function 'balance_of' was not foundin this contract's abi. ", 'Are you sure you provided the correct contract abi?')

**更新**我擺脫了上述異常，現在我得到以下異常：

send_address = "0xF35A192475527f80EfcfeE5040C8B5BBB596F69A"
balance = instance.functions.balanceOf.call(send_address)
#Error :
call_transaction = dict(**transaction)
TypeError: type object argument after ** must be a mapping, not str

如果我嘗試這個：

send_address = "0xF35A192475527f80EfcfeE5040C8B5BBB596F69A"
balance = instance.functions.balanceOf.call({'from':send_address})
#Error:
AttributeError: 'balanceOf' object has no attribute 'args'

Answer 1

您必須查看合約是否具有“balance_of”功能。 執行時

balance = instance.functions.balanceOf.call(send_address)

您正在執行合約的 balance_of 功能，如果合約沒有該功能，則會出現錯誤

Answer 2

在最后一個代碼示例中，嘗試將第二行修改為： balance = instance.functions.balanceOf().call({'from':send_address}) 。 平衡后的括號是您要傳遞給solidity函數的參數。

Answer 3

這在今天肯定有效：

send_address = "0xF35A192475527f80EfcfeE5040C8B5BBB596F69A"
balance = instance.functions.balanceOf(send_address).call()