Get index of lines that match my linq

Question

I have a linq statement and I would like to know if it is possible to get indicies of lines that match my statement? Here it is:

var result = list3.Where(middle          


        

Answer 1

do you mean this?

var result = list3.Where(middle => list4.Any(x => x == middle.Middle.category1))
           .Select(obj => new { obj, dt = DateTime.ParseExact(obj.LeftColumn, dateFormat, CultureInfo.InvariantCulture) })
           .Where(x => x.dt >= czas11 && x.dt <= czas22)
           .Select((x,index) =>new{ x.obj,Index=index}).ToList();