Looking for a simple standalone persistent dictionary implementation in C# [closed]

Answer 1

Like Douglas said, you need to know the fixed size of your types (both T and V). Also, variable-length instances in the object grid referenced by any of those instances are out.

Still, implementing a dictionary backed by a file is quite simple and you can use the BinaryWriter class to write the types to disk, after inheriting or encapsulating the Dictionary<TKey, TValue> class.

Answer 2

Let me analyze this:

1. Retrieve information by key
2. Persistant storage
3. Do not want to write back the whole file when 1 value changes
4. Should survive crashes

I think you want a database.

Edit: I think you are searching for the wrong thing. Search for a database that fits your requirements. And change some of your requirements, because I think it will be difficult to meet them all.

Answer 3

I don't know of anything to solve your problem. It will need to be a fixed size structure, so that you can meet the requirements of being able to rewrite records without rewriting the entire file.

This means normal strings are out.

Answer 4

Just use serialization. Look at the BinaryFormatter class.

Answer 5

Sounds cool, but how will you get around changes to the stored value (if it was a reference type) itself? If its immutable then all is well but if not you're kinda stuffed :-)

If you're not dealing with immutable values, I would suspect a better approach would be to handle persistence at the value level and to just rebuild the dictionary as necessary.

(edited to add a clarification)

Answer 6

Check this blog out:

http://ayende.com/Blog/archive/2009/01/17/rhino.dht-ndash-persistent-amp-distributed-storage.aspx

Looks to be exactly what you are looking for.