Javascript中的Caesar密码

function caesarEncrypt(text, shift) {
    let result = '';
    for (let i = 0; i < text.length; i++) {
        let char = text[i];
        if (char.match(/[a-z]/i)) {
            let code = text.charCodeAt(i);
            // 大写字母
            if (code >= 65 && code <= 90) {
                char = String.fromCharCode(((code - 65 + shift) % 26) + 65);
            }
            // 小写字母
            else if (code >= 97 && code <= 122) {
                char = String.fromCharCode(((code - 97 + shift) % 26) + 97);
            }
        }
        result += char;
    }
    return result;
}

function caesarDecrypt(ciphertext, shift) {
    return caesarEncrypt(ciphertext, -shift);
}

// 示例使用
let plaintext = "Hello, World!";
let shift = 3;
let encrypted = caesarEncrypt(plaintext, shift);
let decrypted = caesarDecrypt(encrypted, shift);

console.log("Plaintext: ", plaintext);
console.log("Encrypted: ", encrypted);
console.log("Decrypted: ", decrypted);