using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        List<ITag> tagList = new List<ITag>(); // Create five tags, and add them to a list.

        tagList.Add(new Tag("0", null, true));

        tagList.Add(new Tag("1", null, true));

        tagList.Add(new Tag("2", null, true));

        tagList.Add(new Tag("3", null, true));

        tagList.Add(new Tag("4", null, true));

        Console.WriteLine("Tag list 1");

        foreach (Tag t in tagList)

        {

            Console.WriteLine("Address: " + t.Address + ", Value: " + t.Value + ", Functional: " + t.Status); // Show tagList on console.

        }

        //Console.ReadKey();

        PLCInterface2.setPLCTagValues(tagList);

    }

}

​

public interface ITag

{

    string Address { get; set; }

    string Value { get; set; }

    bool Status { get; set; }

}

​

public class Tag : ITag

{

    public string Address { get; set; }

    public string Value { get; set; }

    public bool Status { get; set; }

    public Tag(string address, string val, bool status)

    {

        Address = address;

        Value = val;

        Status = status;

    }

}

​

public class PLCInterface2

{

    public static List<ITag> PLCTagList = new List<ITag>();

    public static List<ITag> setPLCTagValues(List<ITag> tagList)

    {

        List<ITag> returnList = new List<ITag>();

        foreach (ITag addTag in tagList) // Add tags that don't exist in PLCTagList yet.

        {

            if (!(PLCTagList.Exists(tag => tag.Address == addTag.Address)))

            {

                PLCTagList.Add(addTag);

            }

            else { }

        }

        foreach (ITag UITag in tagList) // Set the value of the corresponding PLC tag.

        {

            foreach (ITag PLCTag in PLCTagList)

            {

                if (UITag.Address == PLCTag.Address)

                {

                    PLCTag.Value = UITag.Value;

                    returnList.Add(UITag);

                }

                else { }

            }

        }

        foreach (ITag PLCTag in PLCTagList) // If value is null, set tag to disfunctional.

        {

            if (PLCTag.Value == null)

            {

                PLCTag.Status = false;

            }

            else

            {

                PLCTag.Status = true; // Vice versa

            }

        }

        return returnList;

    }

    public static List<ITag> getPLCTagValues(List<ITag> tagList)

    {

        List<ITag> returnList = new List<ITag>();

        foreach (ITag addTag in tagList) // Add tags that don't exist in PLCTagList yet.

        {

            if (!(PLCTagList.Exists(PLCTag => PLCTag.Address == addTag.Address)))

            {

                PLCTagList.Add(addTag);

            }

            else { }

        }

        foreach (ITag PLCTag in PLCTagList) // If value is null, set tag to disfunctional.

        {

            if (PLCTag.Value == null)

            {

                PLCTag.Status = false;

            }

            else

            {

                PLCTag.Status = true; // Vice versa

            }

        }

        foreach (ITag UITag in tagList) // Add corresponding tags from PLC tag list to a return list.

        {

            foreach (ITag PLCTag in PLCTagList)

            {

                if (UITag.Address == PLCTag.Address)

                {

                    returnList.Add(PLCTag);

                }

            }

        }

        return returnList;

    }

}