Question

I have a RegistryKey as a Key for my dictionary.

I cannot seem to set a value for that specific Key. Whatever I do, I keep getting a KeyNotFoundException. The Key does exist, I created it one line earlier

e.g:

public Dictionary<RegistryKey, Dictionary<string, object>> subKeyNodes = new...
subKeyNodes.Add(mainKeyNode.CreateSubKey(keyName),new Dictionary<string, object>());
subKeyNodes[mainKeyNode.CreateSubKey(keyName)].Add("ROAR", "value");

The Add works fine. Adding with that key value always fails and I cannot seem to figure it out.

Answer 1

RegistryKey has neither a GetHashCode nor Equals override. This means instances of RegistryKey will use the default implementation (defined in Object). Because of this two instances of RegistryKey will not be identified as ‘equal’ even if their fields are the same. This means you cannot use instances of this class as a key to hashed based collections such as Dictionary or HashSet.

As a workaround, you could define another class that wraps RegistryKey and defines these method overrides.