How to group dates by week?

Question

I am writing an Excel exporter for a bespoke application I am creating, and I have a question about LINQ grouping in C#.

Basically, this new Excel exporter class is

Answer 1

I tried like this (and it's working :) )

@foreach (var years in _dateRange.GroupBy(y => y.Year))
{
    
@years.Key
    foreach (var months in years.GroupBy(m => m.Month))
    {
        
@CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(months.Key)
        foreach (var weeks in months.GroupBy(w => w.AddDays(-(int)w.DayOfWeek)))
        {
            
@weeks.Key.ToString("dd-MMM-yy")
        }
    }
}