File size: 1,384 Bytes
760f698 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 | function caesarCipher(text, shift) {
let result = "";
for(let i = 0; i < text.length; i++){
let char = text[i];
if(char >= 'A' && char <= 'Z'){
result += String.fromCharCode(
((char.charCodeAt(0) - 65 + shift + 26) % 26) + 65
);
}
else if(char >= 'a' && char <= 'z'){
result += String.fromCharCode(
((char.charCodeAt(0) - 97 + shift + 26) % 26) + 97
);
}
else{
result += char;
}
}
return result;
}
function encryptText(){
let text =
document.getElementById("inputText").value;
let shift =
parseInt(document.getElementById("shift").value);
if(text.trim() === ""){
alert("Please enter text!");
return;
}
if(isNaN(shift)){
alert("Please enter shift key!");
return;
}
let encrypted =
caesarCipher(text, shift);
document.getElementById(
"encryptedOutput"
).innerText = encrypted;
}
function decryptText(){
let text =
document.getElementById("encryptedOutput").innerText;
let shift =
parseInt(document.getElementById("shift").value);
if(text === "---"){
alert("Encrypt text first!");
return;
}
let decrypted =
caesarCipher(text, -shift);
document.getElementById(
"decryptedOutput"
).innerText = decrypted;
}
function clearAll(){
document.getElementById("inputText").value = "";
document.getElementById("shift").value = "";
document.getElementById(
"encryptedOutput"
).innerText = "---";
document.getElementById(
"decryptedOutput"
).innerText = "---";
} |