Node.js中的加密和解密

当我将编码方案指定为’utf-8’时,我得到了预期的结果：@H_675_7@

function encrypt(text) {
        var cipher = crypto.createCipher(algorithm,password)
        var crypted = cipher.update(text,'utf8','hex')
        crypted += cipher.final('hex');
        return crypted;
    }

    function decrypt(text) {
        var decipher = crypto.createDecipher(algorithm,password)
        var dec = decipher.update(text,'hex','utf8')
        dec += decipher.final('utf8');
        return dec;
    }

//text = 'The big brown fox jumps over the lazy dog.'

但是当我试图用’base-64’做它时,它给了我意想不到的结果：@H_675_7@

function encrypt(text) {
    var cipher = crypto.createCipher(algorithm,password)
    var crypted = cipher.update(text,'base64','hex')
    crypted += cipher.final('hex');
    return crypted;
}

function decrypt(text) {
    var decipher = crypto.createDecipher(algorithm,password)
    var dec = decipher.update(text,'base64')
    dec += decipher.final('base64');
    return dec;
}

我无法理解为什么base-64编码方案不接受空格和’.’格式正确.
如果有人知道这一点,请帮助我更好地理解这一点.
任何帮助表示赞赏.@H_675_7@