Question

I have a list (List<a>) that contains a list (List<b>). There is a string field in b type list. I want to to find the indexes of matching strings in list b by searching list a. How can i do that?

public class b
{
    string Word;
    bool Flag;
}

public class a
{
    List<b> BList = new List<b>();
    int Counter;
}

I want to find indexes in list b that matches with the string “Word”.

Answer 1

This Linq Expression return a List of BList and proper finded Index:

        var Result = AList.Select(p => new
        {
            BList = p.BList,
            indexes = p.BList.Select((q, i) => new
            {
                index = i,
                isMatch = q.Word == "Word"
            }
            )
            .Where(q => q.isMatch)
            .Select(q=>q.index)
        });