Protobuf Maps and Dictionaries

As well as dealing with collections, Protobuf can deal with dictionary-like structures. A dictionary (also known as a map) is a data structure that stores a collection of key-value pairs. Because the retrieval of entries is done via the key, each key must be unique.

In C#, the most common way to implement this functionality is via the Dictionary<Tkey, TValue> class from the System.Collections.Generic namespace. In Protobuf, this is achieved via the map<key, value> data type, which we will examine next.

Using map in Protobuf

The following interactive code editor contains the setup with both the gRPC client and server applications we ...