C# XNA MainMenu Class

using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace menu
{
    class MainMenu
    {
        enum GameState { mainMenu, enterCoords, inGame};
            GameState gameState;

        List<MenuElement> main = new List<MenuElement>();
        List<MenuElement> enterCoords = new List<MenuElement>();

        private string Coordinates = string.Empty;
        private SpriteFont font;

        private Keys[] lastPressedKeys = new Keys[5];

        public MainMenu()
        {
            main.Add(new MenuElement("menu"));
            main.Add(new MenuElement("play"));


            enterCoords.Add(new MenuElement("Coords"));
            enterCoords.Add(new MenuElement("done"));

        }

        public void LoadContent(ContentManager content)
        {
            foreach(MenuElement element in main)
            {
                element.LoadContent(content);
                element.CenterElement(500, 800);
                element.clickEvent += OnClick;
            }
            main.Find(x => x.AssetName == "play").MoveElement(0, -100);

            foreach (MenuElement element in enterCoords)
            {
                element.LoadContent(content);
                element.CenterElement(500, 800);
                element.clickEvent += OnClick;
                font = content.Load<SpriteFont>("SpriteFont1");
            }
            enterCoords.Find(x => x.AssetName == "done").MoveElement(0, 60);
        }

        public void Update()
        {
            switch (gameState)
            {
                case GameState.mainMenu:
                    foreach (MenuElement element in main)
                    {
                        element.Update();
                    }
                    break;
                case GameState.enterCoords:
                    foreach (MenuElement element in enterCoords)
                    {
                        element.Update();
                    }
                    break;
                case GameState.inGame:
                    break;
                default:
                    break;
            }

        }

        public void Draw(SpriteBatch spriteBatch)
        {
            switch (gameState)
            {
                case GameState.mainMenu:
                    foreach (MenuElement element in main)
                    {
                        element.Draw(spriteBatch);
                    }
                    break;
                case GameState.enterCoords:
                    foreach (MenuElement element in enterCoords)
                    {
                        element.Draw(spriteBatch);
                    }
                    GetKeys();
                    spriteBatch.DrawString(font, Coordinates, new Vector2(300, 250), Color.Black);

                    break;
                case GameState.inGame:
                    break;
                default:
                    break;

            }

        }
        public void OnClick(string element)
        {
            if (element == "play")
            {
                gameState = GameState.enterCoords;
                //Play the simulation
            }
            if (element == "done")
            {
                gameState = GameState.inGame;
            }
        }

        public void GetKeys()
        {
            KeyboardState kbState = Keyboard.GetState();

            Keys[] pressedKeys = kbState.GetPressedKeys();

            foreach (Keys key in lastPressedKeys)
            {
                if (!pressedKeys.Contains(key))
                {
                    //key is no longer pressed
                    OnKeyUp(key);
                }

            }
            foreach (Keys key in pressedKeys)
            {
                if (!lastPressedKeys.Contains(key))
                {
                    OnKeyDown(key);
                }
            }
            lastPressedKeys = pressedKeys;
        }
        public void OnKeyUp(Keys key)
        {



        }

        public void OnKeyDown(Keys key)
        {
            KeyboardState kbState = Keyboard.GetState();

            if (key == Keys.Back && Coordinates.Length > 0)
            {
                Coordinates = Coordinates.Remove(Coordinates.Length - 1);
            }
            else
            {

                Coordinates += key.ToString();

            }

        }




    }
}