Promise.all完成并出现错误错误：Solidity函数（元掩码）的参数数目无效

Question

I'm currently working on a project that uses Javascript, Async/Await, and Web3 (for Ethereum). I'm looking to create a frontend page that is capable of detecting a user's Metamask address, then using that within a function. I've already gotten something like this to work in a previous page, but I've run into trouble translating it onto another page. I suspect that getCurrentAccount() isn't returning anything, thus messing up the number and type of variables that Promise.all expects to have sent in. The relevant code is:

function isInList(input) {
    return new Promise(function(resolve, reject) {
        myElection.areYouInList(input, function(error, response) {
            if (error) {
                reject(error);
            } else {
                resolve(response);
            }
        })
    });
}

function hasntVotedYet(input) {
    return new Promise(function(resolve, reject) {
        myElection.haveYouVotedAlready(input, function(error, response) {
            if (error) {
                reject(error);
            } else {
                resolve(response);
            }
        })
    });
}

function isNotOver() {
    return new Promise(function(resolve, reject) {
        myElection.isItOver(function(error, response) {
            if (error) {
                reject(error)
            } else {
                resolve(response);
            }

        })
    });
}

async function getCurrentAccount() {
    console.log("getCurrentAccount method");
    web3.eth.getAccounts((err, accounts) => {
        currentAccount = accounts[0]
    })
    return currentAccount; //KEEP IN MIND THAT YOU NEED TO ACTUALLY BE LOGGED INTO METAMASK FOR THIS TO WORK - OTHERWISE IT'LL RETURN UNDEFINED BECAUSE THERE AREN'T ANY ACCOUNTS
}


async function verify() {
    console.log("Verify");
    try {
        -- -- > THIS LINE //
        var myCurrentAccount = await getCurrentAccount();
        console.log("myCurrentAccount is: " + myCurrentAccount);
        data = await Promise.all([isInList(myCurrentAccount), hasntVotedYet(myCurrentAccount), isNotOver()]); //data then equals an array, containing both the strings returned from these two methods
        console.log("success");
        console.log(data)

        if (data[0] && !data[1] && !data[2]) { //check firstly that we are allowed to vote, secondly that we have not already voted, and finally that this vote is not over yet
            var x = document.getElementById("hidden");
            x.style.display = "block";
        } else if (!data[0]) {
            alert("That address was not found in the Whitelist.");
        } else if (data[1]) {
            alert("You have already voted and may not vote a second time");
        } else if (data[2]) {
            alert("This election has already concluded. Votes can no longer validly be cast for it.");
        }
    } catch (error) {
        console.log("Promise.all finished with error " + error)
    }
}

Answer 1

The problem come from the way you get the metamask account : web3.eth.getAccounts is an asynchronous function. Something like that should works :

async function getCurrentAccount() {
    console.log("getCurrentAccount method");
    let accounts = await web3.eth.getAccounts();
    return accounts[0];
}