基于JavaScript实现猜数字游戏代码实例

时间：2021-05-25

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。

<!DOCTYPE html><html> <head> <meta charset="utf-8"> <title>猜数字游戏</title> <style> html { font-family: sans-serif; } body { width: 50%; max-width: 800px; min-width: 480px; margin: 0 auto; } .lastResult { color: white; padding: 3px; } </style> </head> <body> <h1>猜数字游戏</h1> <p>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。</p> <div class="form"> <label for="guessField">请猜数: </label> <input type="text" id="guessField" class="guessField"> <input type="submit" value="确定" class="guessSubmit"> </div> <div class="resultParas"> <p class="guesses"></p> <p class="lastResult"></p> <p class="lowOrHi"></p> </div> <script> // 开始编写 JavaScript 代码 </script> </body></html>

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

<!DOCTYPE html><html><head> <meta charset="utf-8"> <title>猜数字游戏</title> <style> html { font-family: sans-serif; } body { width: 50%; max-width: 800px; min-width: 480px; margin: 0 auto; } .lastResult { color: white; padding: 3px; } </style></head><body> <h1>猜数字游戏</h1> <p>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。</p> <div class="form"> <label for="guessField">请猜数: </label> <input type="text" id="guessField" class="guessField"> <input type="submit" value="确定" class="guessSubmit"> </div> <div class="resultParas"> <p class="guesses"></p> <p class="lastResult"></p> <p class="lowOrHi"></p> </div> <script> 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; } </script></body></html>

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。

声明：本页内容来源网络，仅供用户参考；我单位不保证亦不表示资料全面及准确无误，也不保证亦不表示这些资料为最新信息，如因任何原因，本网内容或者用户因倚赖本网内容造成任何损失或损害，我单位将不会负任何法律责任。如涉及版权问题，请提交至online#300.cn邮箱联系删除。

相关文章