Dictionary with null key?
92735
C# -- Need an IDictionary implementation that will allow a null key
29684
How to check if an object is nullable?
112007
Why can't I use a list as a dict key in python?
58669
What is the best way to implement nested dictionaries?
41685
Can I "fill" an empty object?
65589
How will I be able to remove [NSNull Null] objects from NSMutableArray?
117426
How to find array / dictionary value using key?
85821
What's the best way of implementing a thread-safe Dictionary?
26871
Bidirectional 1 to 1 Dictionary in C#
54143
Why is the default value of the string type null instead of an empty string?
90129
How to check if an NSDictionary or NSMutableDictionary contains a key?
137538
Invert keys and values of the original dictionary
104501
How do I enforce null checking?
48235
Setting Objects to Null/Nothing after use in .NET
22476
One liner: creating a dictionary from list with indices as keys
92187
Unable to cast object of type 'System.DBNull' to type 'System.String`
19941
Enum to dictionary