using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        //Arrange

        //Keys needed to get ValueToGet property

        var key1 = new WidgetA{Id = 1, Key = 52};

        var key2 = new WidgetA{Id = 1, Key = 102};

        var key3 = new WidgetA{Id = 1, Key = 152};

        List<WidgetA> list = new List<WidgetA>();

        list.Add(key1);

        list.Add(key2);

        list.Add(key3);

        //Lookups

        var keyLookup1 = new WidgetB()

        {Id = 1, KeyLookup = 50, ValueLookup = "Fifty"};

        var keyLookup2 = new WidgetB()

        {Id = 2, KeyLookup = 100, ValueLookup = "One hundred"};

        var keyLookup3 = new WidgetB()

        {Id = 3, KeyLookup = 150, ValueLookup = "One hundred and fifty"};

        List<WidgetB> listLookup = new List<WidgetB>();

        listLookup.Add(keyLookup1);

        listLookup.Add(keyLookup2);

        listLookup.Add(keyLookup3);

    //Act

    /* Given a key from list, how do I update the ValueToGet property from the closes KeyLookup in listLookup 

        key1 = Key = 52, ValueToGet = "Fifty"

        */

    }

}

​

public class WidgetA

{

    public int Id { get; set; }

​

    public int Key { get; set; }

​

    public string ValueToGet { get; set; }

}

​

public class WidgetB

{

    public int Id { get; set; }

​

    public int KeyLookup { get; set; }

​

    public string ValueLookup { get; set; }

}