C#

mark_me wrote:

its icon remains and disappears only when i move mouse over it.

public partial class ListToDictionaryTestForm : Form
{
    List<string> testList = new List<string>();

    public ListToDictionaryTestForm()
    {
        InitializeComponent();

        testList.Add("one");
        testList.Add("One");
        testList.Add("two");
        testList.Add("three");
        testList.Add("one");
        testList.Add("three");
        testList.Add("one");

        OutputResults(testList);
    }

    private void OutputResults(List<string> testList)
    {
        var itemcounts = from s in testList
                         group s by s into g
                         select new
                         {
                             key = g.Key,
                             val = g.Count()
                         };
        Dictionary<string, int> results = itemcounts.ToDictionary(k => k.key, v => v.val);

        foreach (KeyValuePair<string, int> kvp in results)
        {
            lboxResults.Items.Add(string.Format("{0} : {1}", kvp.Key, kvp.Value));
        }
    }
}

private void OutputResults(List<string> testList)
{
    Dictionary<string, int> results = (from s in testList
                    group s by s into g
                    select new
                    {
                        key = g.Key,
                        val = g.Count()
                    }).ToDictionary(k => k.key, v => v.val);

    foreach (KeyValuePair<string, int> kvp in results)
    {
        lboxResults.Items.Add(string.Format("{0} : {1}", kvp.Key, kvp.Value));
    }
}

Luc Pattyn wrote:

as Dan points out below, there is a hidden loop in your magic

Luc Pattyn wrote:

FWIW: The only way I see without loops is with recursion

Luc Pattyn wrote:

you'll need stronger lambda magic,

Rand r = new Random();<br />
foreach(var s in lst) dic[rand.Netx()] = s;

Random r = new Random();<br />
Dictionary<int , string> dic = new Dictionary<int , string>();<br />
dic = lst.ToDictionary <string, int>(s => r.Next());

var keyValuePairs = from string key in lst.Distinct() select new KeyValuePair<string, int>(key,
    lst.Count(
        (string str) => (key == str))
    );