Intro

My notes on the Dictionary class used for storing <key, value> pairs.

Tips and Tidbits

• Used to store key/value pairs.

• Size grows dynamically (as opposed to arrays where you need to specify the size ahead of time).

• The dictionary is accessed via the key (similar to an array’s index). Therefore, the key cannot be null, but value can be.

• The values (and keys) must all be the same type. You can’t store a string in one key and an integer in another.

• The key must be unique (ie, duplicate keys are not allowed).

• Retrieving a value by using its key is very fast, close to O(1), because the Dictionary<TKey,TValue> class is implemented as a hash table.