javascript - 将变量更改为全局变量，以便外部警报功能可以使用它

Question

我正在用 JavaScript 为我的学校编写一个小游戏(剪刀石头布)作为家庭元素，最近我遇到了困难。我正在尝试将原始 (let) 变量更改为全局变量，以便外部函数可以看到它们的值。pScore 的值在每一轮中增加，分数得到更新。

我试图将变量从 let 更改为 var，但它不起作用。

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
    );
}

错误:pScore 或 playerScore 未定义

我希望倒计时功能达到 pScore，然后 Alert 最后更新的分数。

Answer 1

我稍微重新安排了您的代码以使其正常工作。

变化

• 从 window.pScore 中删除了 window. 部分。 pScore 变量不是真正的全局变量，而是 game() 函数中的全局变量。
• 将 playerScore 和 computerScore 变量移出 game() 函数，并使它们可供 timer() 函数

    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
    );
}