將變量更改為全局，以便外部警報功能可以使用它

Question

我正在為學校編寫一個JavaScript小游戲（剪刀石頭布），作為一個家庭項目，最近我陷入了困境。 我正在嘗試將原始（ let ）變量更改為全局變量，以便外部函數可以看到它們的值。 pScore的值在每個回合中都會增加，分數會更新。

我試圖將變量從let更改為var ，但是它不起作用。

const game = () => {
    let pScore = 0; //player score
    let cScore = 0; //computer score
    var mScore = 12; // maximal score

    // the Function
    const updateScore = () => {
        const playerScore = document.querySelector(".player-score p");
        const computerScore = document.querySelector(".computer-score p");
        playerScore.textContent = window.pScore;
        computerScore.textContent = cScore;
    };

    //Check for Paper
    if (playerChoice === "paper") {
        if (computerChoice === "scissors") {
            winner.textContent = "computer wins! :(";
            cScore++;
            updateScore();
            return;
        } else {
            winner.textContent = "you won! :)";
            pScore++;
            updateScore();
            if (pScore === mScore) {
                finalScore();
            }
            return;
        }
    }
};

//The Outer function
function timer() {
    var countDown = new Date(Date.now() + 60000).getTime();
    var x = setInterval(
        function () {
            var now = new Date().getTime();
            var distance = countDown - now;

            var seconds = Math.floor((distance % (1000 * 60)) / 1000);

            document.getElementById("timer").innerHTML = seconds;

            if (distance < 0) {
                clearInterval(x);
                alert(un + ' Time is up!' + alert(playerScore.textContent));
                location.reload(true);
            }
        }, 1000
    );
}

錯誤：未定義pScore或playerScore

我希望倒數計時功能達到pScore，然后提醒最后更新的分數。

Answer 1

我已經稍微重新排列了您的代碼以使其正常工作。

變化

• 刪除了window. 來自window.pScore一部分。 pScore變量不是真正的全局變量，而是game()函數中的全局變量。
• 將playerScore和computerScore變量移出game()函數，並使它們可用於timer()函數

    const playerScore = document.querySelector(".player-score p");
    const computerScore = document.querySelector(".computer-score p");
    const game = () => {
    let pScore = 0; //player score
    let cScore = 0; //computer score
    var mScore = 12; // maximal score

    // the Function
    const updateScore = () => {
        playerScore.textContent = pScore;
        computerScore.textContent = cScore;
    };

    //Check for Paper
    if (playerChoice === "paper") {
        if (computerChoice === "scissors") {
            winner.textContent = "computer wins! :(";
            cScore++;
            updateScore();
            return;
        } else {
            winner.textContent = "you won! :)";
            pScore++;
            updateScore();
            if (pScore === mScore) {
                finalScore();
            }
            return;
            }
        }
    };

//The Outer function
function timer() {
    var countDown = new Date(Date.now() + 60000).getTime();
    var x = setInterval(
        function () {
            var now = new Date().getTime();
            var distance = countDown - now;

            var seconds = Math.floor((distance % (1000 * 60)) / 1000);

            document.getElementById("timer").innerHTML = seconds;

            if (distance < 0) {
                clearInterval(x);
                alert(un + ' Time is up!' + alert(playerScore.textContent));
                location.reload(true);
            }
        }, 1000
    );
}