Adds an element with the provided key and value to the IDictionary`2.
| Exception Type | Condition |
|---|---|
| NotSupportedException | The IDictionary`2 is read-only. |
| ArgumentException | An element with the same key already exists in the IDictionary`2. |
| ArgumentNullException | key is null. |
HashList<TKey, TValue> Class | ComponentOwl.BetterListView.Collections Namespace | HashList<TKey, TValue>.Add Overload List