This may be asking a lot, but please try to help!

I'm trying to create a very simple encryption DLL for use in a Visual Basic program.

The encryptor works by having one function to set the random number seed using 'srand'. The other function will encrypt an array of bytes by xor-ing them with rand()/128. I hope that explained it well enough.

Can anyone give me an idea of how this can be done so the DLL can be called from within a Visual Basic program?