基於JavaScript實現猜數字遊戲程式碼例項
阿新 • • 發佈:2020-07-31
環境
- vscode 1.46
- Microsoft Edge 83
示例
以下內容為了解和熟悉 JavaScript,不需要理解,能夠複製貼上並正確執行即可。
新建網頁模板
在 vscode 中新建一個 index.html 檔案,然後輸入以下內容。
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>猜數字遊戲</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>猜數字遊戲</h1> <p>我剛才隨機選定了一個100以內的自然數。看你能否在 10 次以內猜中它。每次我都會告訴你所猜的結果是高了還是低了。</p> <div class="form"> <label for="guessField">請猜數: </label> <input type="text" id="guessField" class="guessField"> <input type="submit" value="確定" class="guessSubmit"> </div> <div class="resultParas"> <p class="guesses"></p> <p class="lastResult"></p> <p class="lowOrHi"></p> </div> <script> // 開始編寫 JavaScript 程式碼 </script> </body> </html>
定義變數
首先將需要使用的變數都定義出來。
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;
定義猜數字主邏輯
function checkGuess() { let userGuess = Number(guessField.value); if (guessCount === 1) { guesses.textContent = '上次猜的數:'; } guesses.textContent += userGuess + ' '; if (userGuess === randomNumber) { lastResult.textContent = '恭喜你!猜對了'; lastResult.style.backgroundColor = 'green'; lowOrHi.textContent = ''; setGameOver(); } else if (guessCount === 10) { lastResult.textContent = '!!!GAME OVER!!!'; setGameOver(); } else { lastResult.textContent = '你猜錯了!'; 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(); }
結束遊戲
function setGameOver() { guessField.disabled = true; guessSubmit.disabled = true; resetButton = document.createElement('button'); resetButton.textContent = '開始新遊戲'; document.body.appendChild(resetButton); resetButton.addEventListener('click',resetGame); }
重置遊戲
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; }
瀏覽器開啟
用瀏覽器開啟剛剛編寫的程式,試試遊戲是否能夠正常執行。
附錄
原始碼
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>猜數字遊戲</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>猜數字遊戲</h1> <p>我剛才隨機選定了一個100以內的自然數。看你能否在 10 次以內猜中它。每次我都會告訴你所猜的結果是高了還是低了。</p> <div class="form"> <label for="guessField">請猜數: </label> <input type="text" id="guessField" class="guessField"> <input type="submit" value="確定" 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 = '上次猜的數:'; } guesses.textContent += userGuess + ' '; if (userGuess === randomNumber) { lastResult.textContent = '恭喜你!猜對了'; lastResult.style.backgroundColor = 'green'; lowOrHi.textContent = ''; setGameOver(); } else if (guessCount === 10) { lastResult.textContent = '!!!GAME OVER!!!'; setGameOver(); } else { lastResult.textContent = '你猜錯了!'; 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 = '開始新遊戲'; 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內容,希望對大家的學習有所幫助,也希望大家多多支援我們。