I'm trying to make an alert popup when I press a sequence of keys on my website, for example if I write "420" on my keyboard I want a message to popup saying "You made it" or something. I get it when I use only 2 keypresses using this:
if (e.ctrlKey && e.keyCode == 90) {
alert("Sweet");
}
});
Which is the CTRL-key + letter Z, but I cant seem to understand how to make it work if I want it to be the correct sequence of 4 2 0 or something similar. And I'm only allowed to use JavaScript.
For that to work, you need to keep track of keys pressed.
Here, I add every key pressed to a variable str at that variable's end, and then cut off everything except the last 3 characters.
let str = '';
window.addEventListener('keyup', function(event) {
str = `${str}${event.key}`.substr(-3);
if (str === '420') console.log('You made it!');
})Simultaneous keys (like ctrl+Z) is different to a sequence (like 420).
One of many strategies could be to split the sequence into an array and use a copy of it (temp) to shift that sequence when the first element is typed.
let targetSequence = "420".split("")
let temp = [...targetSequence]
document.querySelector("#test").addEventListener("keyup", function(e) {
if (temp[0] == e.key) {
temp.shift()
} else {
temp = [...targetSequence]
}
console.log(temp)
// If the sequence was done
if (!temp.length) {
console.log("--- You did it! ---")
temp = [...targetSequence]
}
})<input id="test">