dictionary int list c# code example

Example 1: how to create dictionary of list in c#

public static void Main()
        {
            Dictionary<String, List<string>> dic = new Dictionary<string, List<string>>();

            List<string> li1 = new List<string>();
            li1.Add("text1"); li1.Add("text2"); li1.Add("text3"); li1.Add("text4");

            List<string> li2 = new List<string>();
            li2.Add("text1"); li2.Add("text2"); li2.Add("text3"); li2.Add("text4");

            dic["1"] = li1;
            dic["2"] = li2;


            foreach (string key in dic.Keys)
            {
                foreach (string val in dic[key])
                {
                    Console.WriteLine(val);
                }
            }
        }

Example 2: dictionary string list int c#

//init
Dictionary<string, List<int>> dictionaryStringListOfInt = new Dictionary<string, List<int>>(){
                { "The First", new List<int>(){ 1,2 } },
                { "The Second", new List<int>(){ 1,2 } }
            };
//add a dictinary Key Value pair with a new empty list
//note you can add an existing list but be carful as it is a ref type and only pointing to ints (changes will be seen in original list ref)
dictionaryStringListOfInt.Add("The New", new List<int>());
//Add some values
dictionaryStringListOfInt["The New"].Add(1);
dictionaryStringListOfInt["The New"].Add(2);
//access some values via the Key and the values index
Console.WriteLine(dictionaryStringListOfInt["The New"][0]);//expected output 1
dictionaryStringListOfInt["The New"][0] = 3;
Console.WriteLine(dictionaryStringListOfInt["The New"][0]);//expected output 3
Console.WriteLine(dictionaryStringListOfInt["The New"][1]);//expected output 2