Question

I need a class that will work like C++ std::map. More specifically, I need such a behavior:
map< string, vector<int> > my_map;
Is it possible?

Answer 1

A dictionary is I believe what you want:

Dictionary<String, int> dict = new Dictionary<String, int>();

dict.Add("key", 0);
Console.WriteLine(dict["key"]);

etc, etc

MSDN: http://msdn.microsoft.com/en-us/library/xfhwa508.aspx

You can specify more or less any type as the key/value type. Including another dictionary, an array, or whatever:

Dictionary<String, String[]> dict = new Dictionary<String, String[]>();

So here each element in the Dictionary points to an array of strings.

To implement what you require (with the vector int), you would require a List as the value type:

Dictionary<String, List<int>> dict = new Dictionary<String, List<int>>();

It is worth noting that a Dictionary has no predefined order, whereas std::map does. If order is important, you may want to use SortedDictionary instead, which is almost identical in usage, but sorts on the key. All depends if you plan to iterate over the dictionary really.

Note however that if you use a class you created as the key, you will need to properly override GetHashCode and Equals.