Can a base64 encoded string contain whitespace?

Question

Might a base64 encoded string contain whitespace? Specifically, could it contain whitespace at the end of the string?

PS. I\'m thinking about the whole \"My

Answer 1

It shouldn't, but it might do.

A valid base64 string should not contain whitespace since the encoding alphabet should only consist of A-Z a-z 0-9 + /

However, if the encoded data happens to contain a '+' character, and the data is passed in a URL, it can be unintentionally converted into a space. So you may come across a supposed base64 string that appears to have spaces in it under these circumstances.

If this is the case, simply replace spaces with pluses before decoding.

PS. I'm thinking about the whole "MySQL will trim trailing whitespace when storing strings in VARCHAR fields" here

As an aside, the trailing whitespaces of a varchar won't be casually stripped as of MySQL 5.0.3