I am currently developing my own JSON Library for Delphi. There are already libraries for that, but none of them suited my needs.
There is the built-in DBXJSON, which is used in the DataSnap part of Delphi. However, it is a bit of a hassle to work with.
There is
TlkJSON from Simon Stuart, which has (or had, I don't know the current status) some problems with Umlauts (ä,ö,ü,ß, etc.)
There is the
Delphi Web Utils from Jose Fabio N Almeida, which has some memory issues and other bugs, and most importantly, does not work well under XE2. It also hasn't been updated for a while.
And there is the
SuperObject which is very powerful, but it has IMO a horrible syntax.
Since I was using the Delphi Web Utils before and I didn't want to rewrite all my other code when switching libraries, I designed my Interfaces and Classes in a similar way, e.g. the objects and array have methods named "Put" and "GetString".
I have released
my library on Google Code. You can check it out via subversion or you can download the zipfile. Any feedback or help is appreciated.
It uses Generics, Rtti (for TValue) and Regular Expressions, which is why it is targeted only for newer versions of Delphi (XE and XE2).