C# LINQ counting elements with DISTINCT
18,768
Solution 1
use group by
var dateGrouped = dates.GroupBy(x => x.Key)
.Select(x => new { Date = x.Key, Values = x.Distinct().Count() });
Solution 2
Below is the solution with complete example
var list = new[]
{
new {Date = new DateTime(2013,07,12), value = 10220},
new {Date = new DateTime(2013,07,12), value = 10220},
new {Date = new DateTime(2013,07,12), value = 12220},
new {Date = new DateTime(2013,07,12), value = 11240},
new {Date = new DateTime(2013,07,12), value = 15220},
new {Date = new DateTime(2013,07,13), value = 23220},
new {Date = new DateTime(2013,07,13), value = 35620},
new {Date = new DateTime(2013,07,14), value = 15620},
new {Date = new DateTime(2013,07,14), value = 15620},
};
var res = from l in list group l by new { l.Date } into g select new { g.Key.Date, value = g.Distinct().Count() };
foreach (var item in res)
{
Console.WriteLine(item.Date + " " + item.value);
}
Author by
Ras
Updated on June 19, 2022Comments
-
Ras almost 2 years
I have a collection of KeyValuePair items with DateTime as key and a string as value. Basically my data looks like:
12/07/2013 - 10220 12/07/2013 - 10220 12/07/2013 - 12220 12/07/2013 - 11240 12/07/2013 - 15220 13/07/2013 - 23220 13/07/2013 - 35620 14/07/2013 - 15620 14/07/2013 - 15620
I would like to have a List of how many items (distinct) I've for each days. So the query would result in a:
12/07/2013 - 4 13/07/2013 - 2 14/07/2013 - 1