title: Bidirectional Map in .NET
body: <p>Is there a .NET data structure I could use for bidirectional lookup?</p>
  
  <p>Here's the problem: Serialization. My object contains a field which points to one of 10 predefined static objects. When writing to the file, I write a single character representing which of the 10 objects is being referenced. At this point, I need a lookup datastructure which will allow me to get the character code based on the object being referenced. When deserializing, I need to do the reverse. I can think of a lot of other places where I could use such a data structure.</p>