主页 / 问题 / 965933
Accepted
InstincT
Asked:2020-04-05 20:57:43 +0000 UTC2020-04-05 20:57:43 +0000 UTC

代码中的错误：没有看到变量（喜欢）

  • 772
var displayOfAll = document.getElementById("displayOfAll");
var playButton = document.getElementById("playButton");
var playButtonShadow = document.getElementById("playButtonShadow");
var playButtonPosX = 300;
var playButtonPosY = 350;
var playButtonMovingUpPosY = 350;
var playButtonHeightWhenMovingUp = 100;
var playButtonFontSize = 500;
var moneyNum = 0;
var addMoneyButtonPlus = '+';
var moneyToAdd = 1;
function Play() {
playButton.style.left = playButtonPosX+"px";
playButton.style.top = playButtonPosY+"px";
displayOfAll.removeChild(playButtonShadow);
if (playButtonMovingUpPosY <= 350) {
    var moveUp = setInterval(function movingUp() {
        if (playButtonMovingUpPosY <= 100) {
            if (playButtonMovingUpPosY <= 0) {
            clearInterval(moveUp);
            displayOfAll.removeChild(playButton);
            Main();
            }
            playButtonHeightWhenMovingUp -= 2;
            playButton.style.height = playButtonHeightWhenMovingUp+"px";
            playButtonMovingUpPosY -= 2;
            playButton.style.top = playButtonMovingUpPosY+"px";
            if (playButtonFontSize <=  300) {
                if (playButtonFontSize <= 0) {
                    playButtonFontSize = 0;
                } else {
                    playButtonFontSize -= 300;
                    playButton.style.fontSize = playButtonFontSize+"%";
                }
            } else {
                playButtonFontSize -= 5;
                playButton.style.fontSize = playButtonFontSize+"%";
            }
        } else {
            playButtonMovingUpPosY -= 2;
            playButton.style.top = playButtonMovingUpPosY+"px";
        }
    }, 1)
}
}
function Main() {
var moneyDiv = document.createElement("div");
moneyDiv.style = "margin:0px;padding:0px;position:absolute;height:100px;width:200px;background-color:green;font-size:500%;text-align:center;top:100px;left:275px;z-index:10;";
displayOfAll.appendChild(moneyDiv);
moneyDiv.innerHTML = "0";
var addMoneyButton = document.createElement("div");
addMoneyButton.style = "margin:0px;padding:0px;position:absolute;height:100px;width:200px;background-color:green;font-size:500%;text-align:center;top:500px;left:275px;z-index:10;";
addMoneyButton.innerHTML = addMoneyButtonPlus;
addMoneyButton.onclick = addMoney;
displayOfAll.appendChild(addMoneyButton);
}
function addMoney() {
moneyNum += moneyToAdd;
moneyDiv.innerHTML = moneyNum;
}

在倒数第二行（“moneyDiv.innerHTML = moneyNum;”）中，浏览器编辑器给出错误“Uncaught ReferenceError: moneyDiv is not defined at HTMLDivElement.addMoney”这里有什么问题？为什么他看不到变量？

javascript

1 个回答

  1. Best Answer

    变量应该在函数的范围内addMoney，现在它在function Main()

    移动变量声明

    var moneyDiv;

    例如，在脚本的最开始，并且在函数内部Main()它必须已经被初始化：

    function Main(){
    moneyDiv = document.createElement("div");
    .....
}

    在这些手势之后，函数addMoney会看到变量moneyDiv

    PS：当一个函数可以访问在它之外定义的变量时，并且在更高的范围内，这称为闭包。您可以在此处closure阅读有关闭包的更多信息

    • 1

相关问题