Dictionary.Clear()
will remove all of the KeyValue
pairs within the dictionary. Doing new Dictionary()
will create a new instance of the dictionary.
If, and only if, the old version of the dictionary is not rooted by another reference, creating a new dictionary will make the entire dictionary, and it's contents (which are not rooted elsewhere) available for cleanup by the GC.
Dictionary.Clear()
will make the KeyValue
pairs available for cleanup.
In practice, both options will tend to have very similar effects. The difference will be what happens when this is used within a method:
void NewDictionary(Dictionary<string,int> dict)
{
dict = new Dictionary<string,int>(); // Just changes the local reference
}
void ClearDictionary(Dictionary<string,int> dict)
{
dict.Clear();
}
// When you use this...
Dictionary<string,int> myDictionary = ...; // Set up and fill dictionary
NewDictionary(myDictionary);
// myDictionary is unchanged here, since we made a new copy, but didn't change the original instance
ClearDictionary(myDictionary);
// myDictionary is now empty
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