Groupby multiple date properties by month and year in LINQ

Question

I need to group by multiple properties by month and year in C# LINQ

This is my code:

public class Class1
{
    public Nulla         


        

Answer 1

If you have MoreLinq referenced you can use make Ivan's answer cleaner by using CountBy:

var result = listGoogleTimezone
    .SelectMany(x => new[] { x.dt1, x.dt2 }
        .Where(dt => dt != null)
        .Select(dt => dt.Value))
    .CountBy(x => new { Year = x.Year, Month = x.Month });

This will can you an IEnumerable> where the TKey is an anonymous type with Year and Month and the int is the count.