.net: Shorten a string, store it as a new string, and later 'rehydrate'

Question

I have an application that stores each user role as a comma-delimited string in the userData portion of the forms authentication ticket.

We have run into a situation where a user was part of many roles, and those roles all have long names. There is a maximum # of characters that you can put into the userData, likely a limitation of cookies.

So, is there a low-cost way I can shorten this string and 'rehydrate' it later?

Unforunately, the userData portion of the ticket is a string - if it were an object I could store it as byte[] and use System.Text.Encoding.Unicode.GetString() later.

I guess this is really a question about being able to shorten a string, store it as a string, and rehydrate it later without losing its original value.

Answer 1

How about just using the roleId ? If setup properly you could even OR these together to form a single integer containing all the roles.

Answer 2

So, string compression?

I'd start by looking at System.IO.Compression

http://msdn.microsoft.com/en-us/library/system.io.compression.aspx