环境

vscode 1.46

Microsoft Edge 83

示例

以下内容为了解和熟悉 JavaScript，不需要理解，能够复制粘贴并正确运行即可。

新建网页模板

在 vscode 中新建一个 index.html 文件，然后输入以下内容。

猜数字游戏

html {

font-family: sans-serif;

}

body {

width: 50%;

max-width: 800px;

min-width: 480px;

margin: 0 auto;

}

.lastResult {

color: white;

padding: 3px;

}

猜数字游戏

我刚才随机选定了一个100以内的自然数。看你能否在 10 次以内猜中它。每次我都会告诉你所猜的结果是高了还是低了。

// 开始编写 JavaScript 代码

定义变量

首先将需要使用的变量都定义出来。

let randomNumber = Math.floor(Math.random() * 100) + 1;

const guesses = document.querySelector('.guesses');

const lastResult = document.querySelector('.lastResult');

const lowOrHi = document.querySelector('.lowOrHi');

const guessSubmit = document.querySelector('.guessSubmit');

const guessField = document.querySelector('.guessField');

let guessCount = 1;

let resetButton;

定义猜数字主逻辑

function checkGuess() {

let userGuess = Number(guessField.value);

if (guessCount === 1) {

guesses.textContent = '上次猜的数：';

}

guesses.textContent += userGuess + ' ';

if (userGuess === randomNumber) {

lastResult.textContent = '恭喜你！猜对了';

lastResult.style.backgroundColor = 'green';

lowOrHi.textContent = '';

setGameOver();

} else if (guessCount === 10) {

lastResult.textContent = '!!!GAME OVER!!!';

setGameOver();

} else {

lastResult.textContent = '你猜错了！';

lastResult.style.backgroundColor = 'red';

if(userGuess < randomNumber) {

lowOrHi.textContent = '你猜低了！';

} else if(userGuess > randomNumber) {

lowOrHi.textContent = '你猜高了';

}

}

guessCount++;

guessField.value = '';

guessField.focus();

}

结束游戏

function setGameOver() {

guessField.disabled = true;

guessSubmit.disabled = true;

resetButton = document.createElement('button');

resetButton.textContent = '开始新游戏';

document.body.appendChild(resetButton);

resetButton.addEventListener('click', resetGame);

}

重置游戏

function resetGame() {

guessCount = 1;

const resetParas = document.querySelectorAll('.resultParas p');

for (let i = 0 ; i < resetParas.length; i++) {

resetParas[i].textContent = '';

}

resetButton.parentNode.removeChild(resetButton);

guessField.disabled = false;

guessSubmit.disabled = false;

guessField.value = '';

guessField.focus();

lastResult.style.backgroundColor = 'white';

randomNumber = Math.floor(Math.random() * 100) + 1;

}

浏览器打开

用浏览器打开刚刚编写的程序，试试游戏是否能够正常运行。

附录

源码

猜数字游戏

html {

font-family: sans-serif;

}

body {

width: 50%;

max-width: 800px;

min-width: 480px;

margin: 0 auto;

}

.lastResult {

color: white;

padding: 3px;

}

猜数字游戏

我刚才随机选定了一个100以内的自然数。看你能否在 10 次以内猜中它。每次我都会告诉你所猜的结果是高了还是低了。

let randomNumber = Math.floor(Math.random() * 100) + 1;

const guesses = document.querySelector('.guesses');

const lastResult = document.querySelector('.lastResult');

const lowOrHi = document.querySelector('.lowOrHi');

const guessSubmit = document.querySelector('.guessSubmit');

const guessField = document.querySelector('.guessField');

let guessCount = 1;

let resetButton;

function checkGuess() {

let userGuess = Number(guessField.value);

if (guessCount === 1) {

guesses.textContent = '上次猜的数：';

}

guesses.textContent += userGuess + ' ';

if (userGuess === randomNumber) {

lastResult.textContent = '恭喜你！猜对了';

lastResult.style.backgroundColor = 'green';

lowOrHi.textContent = '';

setGameOver();

} else if (guessCount === 10) {

lastResult.textContent = '!!!GAME OVER!!!';

setGameOver();

} else {

lastResult.textContent = '你猜错了！';

lastResult.style.backgroundColor = 'red';

if (userGuess < randomNumber) {

lowOrHi.textContent = '你猜低了！';

} else if (userGuess > randomNumber) {

lowOrHi.textContent = '你猜高了';

}

}

guessCount++;

guessField.value = '';

guessField.focus();

}

guessSubmit.addEventListener('click', checkGuess);

function setGameOver() {

guessField.disabled = true;

guessSubmit.disabled = true;

resetButton = document.createElement('button');

resetButton.textContent = '开始新游戏';

document.body.appendChild(resetButton);

resetButton.addEventListener('click', resetGame);

}

function resetGame() {

guessCount = 1;

const resetParas = document.querySelectorAll('.resultParas p');

for (let i = 0; i < resetParas.length; i++) {

resetParas[i].textContent = '';

}

resetButton.parentNode.removeChild(resetButton);

guessField.disabled = false;

guessSubmit.disabled = false;

guessField.value = '';

guessField.focus();

lastResult.style.backgroundColor = 'white';

randomNumber = Math.floor(Math.random() * 100) + 1;

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。