Can anyone recommend a decent encryption function that works with PHP 3.xx? I want to be able to encrypt a line before I write it to a .txt file, and then de-encrypt it when I read it back, line by line.
Yeah, I know. I could roll one myself, but why bother if a good one already exists. Besides, I'm no expert in this area.
And just out of curiosity, is it possible to add a number to a character, like 'A' + 5 = 'F' in PHP. I used to do this all the time in C, but can't seem to get PHP to do this, even using array indexes. I was trying to implement a simple Julius Caesar encryption scheme at the time.
