How to make an Encode function based on this Decode function?

How to make an Encode function based on this Decode function? I got the source cod开发者_如何转开发e for the Decode function on the internet but I need the Encode function.

All my attempts to make it failed and the original coder isn't available at the moment.

The (original) code:

byte Decode(byte EncodedByte)
{
    EncodedByte ^= (byte)194;
    EncodedByte = (byte)((EncodedByte << 4) | (EncodedByte >> 4));
    return EncodedByte;
}

Just some quick back of the napkin coding the answer should be

byte Encode(byte DecodedByte)
{
    DecodedByte = (byte)((DecodedByte << 4) | (DecodedByte >> 4));
    DecodedByte ^= (byte)194;
    return DecodedByte;
}

Also I agree with Alex this is a trivial Encryption method. Anyone who knows the algorithm can trivially decrypt your message. I would not rely on it for any sensitive information and if this is code for public use some countries have laws that data must have some form of encryption. If I was a judge for the person suing you for a data breach I would call this more of a obfuscation technique then a encryption technique.

byte Encode(byte EncodedByte) 
{ 
    EncodedByte = (byte)((EncodedByte << 4) | (EncodedByte >> 4)); 
    EncodedByte ^= (byte)194; 
    return EncodedByte; 
} 

Why do not you use normal encryption/decryption functions of c#?

Encrypt and decrypt a string