我被要求在我正在进行的网站上实施Konami Code。它应该做到以下几点：
使用javascript实现这一目标的最简单方法是什么？
将下面的代码放在文件js/konami.js中，并在html文件的正文中引用它，如下所示：<script src="js/konami.js"></script>
// a key map of allowed keys
var allowedKeys = {
37: 'left',
38: 'up',
39: 'right',
40: 'down',
65: 'a',
66: 'b'
};
// the 'official' Konami Code sequence
var konamiCode = ['up', 'up', 'down', 'down', 'left', 'right', 'left', 'right', 'b', 'a'];
// a variable to remember the 'position' the user has reached so far.
var konamiCodePosition = 0;
// add keydown event listener
document.addEventListener('keydown', function(e) {
// get the value of the key code from the key map
var key = allowedKeys[e.keyCode];
// get the value of the required key from the konami code
var requiredKey = konamiCode[konamiCodePosition];
// compare the key with the required key
if (key == requiredKey) {
// move to the next key in the konami code sequence
konamiCodePosition++;
// if the last key is reached, activate cheats
if (konamiCodePosition == konamiCode.length) {
activateCheats();
konamiCodePosition = 0;
}
} else {
konamiCodePosition = 0;
}
});
function activateCheats() {
document.body.style.backgroundImage = "url('images/cheatBackground.png')";
var audio = new Audio('audio/pling.mp3');
audio.play();
alert("cheats activated");
}编辑：将序列更改为b，而不是a，b。谢谢你的评论！
编辑2：调用activateCheats后将konamiCodePosition重置为0。谢谢你的评论！
紧凑版：
function onKonamiCode(cb) {
var input = '';
var key = '38384040373937396665';
document.addEventListener('keydown', function (e) {
input += ("" + e.keyCode);
if (input === key) {
return cb();
}
if (!key.indexOf(input)) return;
input = ("" + e.keyCode);
});
}
onKonamiCode(function () {alert('\o/')})我自己的紧凑和清洁版本灵感来自这里的答案：
let cursor = 0;
const KONAMI_CODE = [38, 38, 40, 40, 37, 39, 37, 39, 66, 65];
document.addEventListener('keydown', (e) => {
cursor = (e.keyCode == KONAMI_CODE[cursor]) ? cursor + 1 : 0;
if (cursor == KONAMI_CODE.length) activate();
});
在这种情况下，触发时会调用activate()函数。
Silentdrummer有一个很好的答案。我不完全确定，但我认为最终可能会在输入密集页面时占用太多内存。重置是一个好习惯。无论哪种方式，这是另一种选择。
// Cheat Codes
neededkeys = [38,38,40,40,37,39,37,39,66,65], started = false, count = 0;
$(document).keydown(function(e) {
key = e.keyCode;
if (!started) {
if (key == 38) {
started = true;
}
}
if (started) {
if (neededkeys[count] == key) {
count++;
} else {
reset();
}
if (count == 10) {
reset();
// Do your stuff here
alert('Cheat Codes Activated');
$('body').css('background-color', '#FFA8A8');
// Turn down for what
var s=document.createElement('script');
s.setAttribute('src','https://nthitz.github.io/turndownforwhatjs/tdfw.js');
document.body.appendChild(s);
}
} else {
reset();
}
});
function reset() {
started = false;
count = 0;
}
这是我在3或4年前提出的解决方案。在我的情况下，我选择了keyUp以使其与keyDown事件发生的任何操作分开。此外，无需指定允许哪些键，因为for循环检查哪个键是针对键盘上的所有键释放的。
var konamicode = [38,38,40,40,37,39,37,39,66,65];
var kc=0;
function checker() {
if (kc==10) {
// What you want to occur when code matches goes in here.
kc=0; // This resets the sequence.
alert("It Worked!");
}
}
function keyUp(e) {
var keynum;
if (window.event) { keynum = event.keyCode; }
else if (e.which) { keynum = e.which; }
for (i = 0; i < 222; i++) { // The 222 represents all the keys on the keyboard.
var kx=konamicode[kc]; // kx represents the current position in the code sequence.
if (keynum == i) {
// Checks to see if key matches sequence, and resets sequence if it doesn't.
if (i!=kx){kc=0;} else {kc++;}
}
}
checker();
}
我真的很喜欢Peter的答案，所以我把它命名为namespace并使回调可选。我也使用jquery因为我喜欢它¯\ _（ツ）_ /¯
var Konami = Konami || {};
Konami.key = '38384040373937396665';
Konami.onCode = function(callback) {
var input = '';
$(document).on("keydown", function(e) {
input += ("" + e.keyCode);
if (input === Konami.key) {
if(typeof callback == 'undefined') {
return alert("⬆⬆⬇⬇⬅➡⬅➡🅱🅰");
}
else {
return callback();
}
}
if (!Konami.key.indexOf(input)) return;
input = ("" + e.keyCode);
});
}
Konami.offCode = function() {
$(document).off("keydown");
}
Konami.onCode();<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>作为打字稿模块
const Konami = (() => {
// up, up, down, down, left, right, left, right, b, a, enter
const SEQUENCE: Array<number> = [
38,
38,
40,
40,
37,
39,
37,
39,
66,
65,
13,
];
let head: number = 0;
let isActive: boolean = false;
let callback: Function | undefined;
const start = (cb: Function): void => {
if (isActive) {
return;
}
window.addEventListener("keydown", onKeyDown);
callback = cb;
isActive = true;
};
const stop = (): void => {
if (!isActive) {
return;
}
isActive = false;
window.removeEventListener("keydown", onKeyDown);
};
const onKeyDown = (event) => {
if (event.keyCode === SEQUENCE[head]) {
head++;
if (head === SEQUENCE.length) {
if (callback instanceof Function) {
callback();
}
head = 0;
}
} else {
head = 0;
}
};
return {
start,
stop,
};
})();
export default Konami;
执行：
Konami.start(() => { alert("konami sequence entered!"); });
注意：SEQUENCE是预期输入的数组。通过使用head var，可以保持订单检查和正确输入的数量。如果输入偏离序列，它还提供了一种简单的重启方式。它还消除了对“计数”变量的需求。
要创建自己的“Konami代码”，请在HTML代码中添加以下代码段。 PS：将const secretCode更改为......你想要的:)。使用当前代码，您必须键入“向上箭头”按钮，然后键入“h”，然后键入“i”，最后输入“向下箭头”按钮。
有问题吗？请问。
<script>
const pressed = [];
const secretCode = 'ArrowUphiArrowDown';
window.addEventListener('keyup', (e) => {
console.log(e.key);
pressed.push(e.key);
pressed.splice(-secretCode.length - 1, pressed.length - secretCode.length);
if(pressed.join('').includes(secretCode)) {
console.log("Any quellcode that will be executed if you enter the correct code.");
}
console.log(pressed);
})
</script>