C# Shallow copy Dictionary?

c# dictionary shallow-copy
Georges Oates Larsen picture Georges Oates Larsen · Jan 14, 2012 · Viewed 16k times · Source

I need to shallow copy a dictionary in c#.

For instance:

Dictionary<int,int> flags = new Dictionary<int,int>();
flags[1] = 2;
flags[2] = 3;
flags[0] = 9001;
Dictionary<int,int> flagsn = flags.MemberwiseClone();

Unfortunately, that returns the error: "error CS1540: Cannot access protected member object.MemberwiseClone()' via a qualifier of typeSystem.Collections.Generic.Dictionary'. The qualifier must be of type `PointFlagger' or derived from it"

Not entirely sure what this means... Is there another way to shallow copy a dictionary/fix my code above?

Answer

JaredPar picture JaredPar · Jan 14, 2012

To get a shallow copy, just use the constructor of Dictionary<TKey, TValue> as it takes an IEnumerable<KeyValuePair<TKey, TValue>>. It will add this collection into the new instance. 

Dictionary<int, int> flagsn = new Dictionary<int, int>(flags);

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