|
<!DOCTYPE html>
<html lang="en-US">
<head>
<meta charset="utf-8">
<title>Number guessing game</title>
<style>
html {
font-family: sans-serif;
}
body {
width: 50%;
max-width: 800px;
min-width: 480px;
margin: 0 auto;
}
.form input[type="number"] {
width: 200px;
}
.lastResult {
color: white;
padding: 3px;
}
</style>
</head>
<body>
<h1>Number guessing game</h1>
<p>We have selected a random number between 1 and 100. See if you can guess it in 10 turns or fewer. We'll tell you if your guess was too high or too low.</p>
<div class="form">
<label for="guessField">Enter a guess: </label>
<input type="number" min="1" max="100" required id="guessField" class="guessField">
<input type="submit" value="Submit guess" 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() {
const userGuess = Number(guessField.value);
if (guessCount === 1) {
guesses.textContent = 'Previous guesses: ';
}
guesses.textContent += userGuess + ' ';
if (userGuess === randomNumber) {
lastResult.textContent = 'Congratulations! You got it right!';
lastResult.style.backgroundColor = 'green';
lowOrHi.textContent = '';
setGameOver();
} else if (guessCount === 10) {
lastResult.textContent = '!!!GAME OVER!!!';
lowOrHi.textContent = '';
setGameOver();
} else {
lastResult.textContent = 'Wrong!';
lastResult.style.backgroundColor = 'red';
if(userGuess < randomNumber) {
lowOrHi.textContent = 'Last guess was too low!' ;
} else if(userGuess > randomNumber) {
lowOrHi.textContent = 'Last guess was too high!';
}
}
guessCount++;
guessField.value = '';
guessField.focus();
}
guessSubmit.addEventListener('click', checkGuess);
function setGameOver() {
guessField.disabled = true;
guessSubmit.disabled = true;
resetButton = document.createElement('button');
resetButton.textContent = 'Start new game';
document.body.appendChild(resetButton);
resetButton.addEventListener('click', resetGame);
}
function resetGame() {
guessCount = 1;
const resetParas = document.querySelectorAll('.resultParas p');
for (const resetPara of resetParas) {
resetPara.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>
산술연산자
연산자 | 이름 | 예제 |
+ | 더하기 | 6 + 9 |
- | 빼기 | 12 - 3 |
* | 곱하기 | 4 * 3 |
/ | 나누기 | 10 / 5 |
복합할당 연산자
: number1과 number2 식의 결과값이 같음
let number1 = 1;
number1 += 2;
let number2 = 1;
number2 = number2 + 2;
비교연산자
연산자 | 이름 | 예제 |
=== | 엄격한 일치 (정확히 같은가?) | 5 === 2 + 4 // false 'Chris' === 'Bob' // false 5 === 2 + 3 // true 2 === '2' // false, 숫자와 문자열은 다름 |
!== | 불일치 (같지 않은가?) | 5 !== 2 + 4 // true 'Chris' !== 'Bob' // true 5 !== 2 + 3 // false 2 !== '2' // true, 숫자와 문자열은 다름 |
< | 미만 | 6 < 10 // true 20 < 10 // false |
> | 초과 | 6 > 10 // false 20 > 10 // true |
출처: https://developer.mozilla.org/ko/docs/Learn/JavaScript/First_steps/A_first_splash
JavaScript에 발 담그기 - Web 개발 학습하기 | MDN
JavaScript에 관한 약간의 이론과, JavaScript가 할 수 있는 일을 알아봤으니 이제 간단한 JavaScript 프로그램을 만들어보면서 개발 과정이 어떤 느낌인지 알아보겠습니다. "숫자 알아맞히기" 게임을 차
developer.mozilla.org