using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        // To be able to filter a nested collection

        // All classes have a property 'Name'

        // Filter along the branch for any that match and return only the mathching items in the same format

        List<Collection> AllCollections = new List<Collection>();

        Collection CollectionA = new Collection();

        Collection CollectionB = new Collection();

        CollectionA.Repos = new List<Repo>{new Repo{Name = "FirstRepo", Workflows = new List<Workflow>{new Workflow{Name = "CI-CD"}, new Workflow{Name = "Tests"}, new Workflow{Name = "First-Ops"}}}, new Repo{Name = "SecondRepo", Workflows = new List<Workflow>{new Workflow{Name = "CI-CD"}, new Workflow{Name = "Testing"}, new Workflow{Name = "Second-Ops"}}}, new Repo{Name = "ThirdRepo", Workflows = new List<Workflow>{new Workflow{Name = "CI-CD"}, new Workflow{Name = "Testers"}, new Workflow{Name = "Third-Ops"}}}};

        CollectionB.Repos = new List<Repo>{new Repo{Name = "FronEndUI", Workflows = new List<Workflow>{new Workflow{Name = "CD"}, new Workflow{Name = "UI-Tests"}, new Workflow{Name = "first-Op"}}}, new Repo{Name = "API", Workflows = new List<Workflow>{new Workflow{Name = "CI"}, new Workflow{Name = "Testing"}, new Workflow{Name = "second-Op"}}}, new Repo{Name = "VisualBasic", Workflows = new List<Workflow>{new Workflow{Name = "Deploy"}, new Workflow{Name = "Copy"}, new Workflow{Name = "third-Op"}}}};

        AllCollections.Add(CollectionA);

        AllCollections.Add(CollectionB);

        // Filter 

        string FilterString = "";  // string FilterString = "Copy" , should return  AllCollections > CollectionB > Repo VisualBasic > Workflow Deploy

        // Result should be List of collections > List of Repos > List of workflows

        var result = AllCollections.SelectMany(c => c.Repos.Where(r => r.Name.Contains(FilterString.ToLower())).ToList().SelectMany(w => w.Workflows.Where(w => w.Name.Contains(FilterString)))).ToList();

        // Dont know how to show nested list in a table sorry

        // This is returning the workflows but not the parent Repo and Repo's Parent, The Collection

        FiddleHelper.WriteTable(result);

    }

}

​

public class Collection

{

    public string Name { get; set; }

​

    public List<Repo> Repos { get; set; }

}

​

public class Repo

{

    public string Name { get; set; }

​

    public List<Workflow> Workflows { get; set; }

}

​

public class Workflow

{

    public string Name { get; set; }

}