[ تمت الإجابة ]ارجو المساعدة في تحريك الاجسام

السلام عليكم

انا لدي احدى كتب لتعليم برمجة الالعاب بXNA و حبيت استفسر عن التحكم بالاجسام بواسطة الكيبورد ,, سويت كل شي لكن مو راضي يتنفذ مثل ما هو مطلوب, ماني عارف هل الكود فيه خطأ منطقي او لا و هذا هو الكود:

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;
using Microsoft.Xna.Framework.Net;
using Microsoft.Xna.Framework.Storage;

namespace WindowsGame3
{
    /// <summary>
    /// This is the main type for your game
    /// </summary>
    public class Game1 : Microsoft.Xna.Framework.Game
    {
        GraphicsDeviceManager graphics;
        SpriteBatch spriteBatch;
        Texture2D texture;
        Texture2D textureT;
        int speed = 20;
        Vector2 post =new Vector2(300,300);
        KeyboardState state = Keyboard.GetState();
        public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
        }

        /// <summary>
        /// Allows the game to perform any initialization it needs to before starting to run.
        /// This is where it can query for any required services and load any non-graphic
        /// related content.  Calling base.Initialize will enumerate through any components
        /// and initialize them as well.
        /// </summary>
        protected override void Initialize()
        {
            // TODO: Add your initialization logic here

            base.Initialize();
        }

        /// <summary>
        /// LoadContent will be called once per game and is the place to load
        /// all of your content.
        /// </summary>
        protected override void LoadContent()
        {
            // Create a new SpriteBatch, which can be used to draw textures.
            spriteBatch = new SpriteBatch(GraphicsDevice);
            texture = Content.Load<Texture2D>(@"images/images");
            textureT = Content.Load<Texture2D>(@"images/كرة");

            // TODO: use this.Content to load your game content here
        }

        /// <summary>
        /// UnloadContent will be called once per game and is the place to unload
        /// all content.
        /// </summary>
        protected override void UnloadContent()
        {
            // TODO: Unload any non ContentManager content here
        }

        /// <summary>
        /// Allows the game to run logic such as updating the world,
        /// checking for collisions, gathering input, and playing audio.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Update(GameTime gameTime)
        {
            // Allows the game to exit
            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
            {
                this.Exit();
            }
            if(state.IsKeyDown(Keys.Right))
                post.X+=speed;
            if (state.IsKeyDown(Keys.Left))
                post.X -= speed;
            if(state.IsKeyDown(Keys.Up))
                post.Y-=speed;
            if (state.IsKeyDown(Keys.Down))
                post.Y += speed;


            // TODO: Add your update logic here

            base.Update(gameTime);
        }

        /// <summary>
        /// This is called when the game should draw itself.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Draw(GameTime gameTime)
        {
            GraphicsDevice.Clear(Color.Black);
            spriteBatch.Begin(SpriteBlendMode.Additive, SpriteSortMode.BackToFront, SaveStateMode.None);
            spriteBatch.Draw(texture, post, null, Color.White, 0, Vector2.Zero, 1, SpriteEffects.None, 0);
            spriteBatch.Draw(textureT, Vector2.Zero, null, Color.White, 0, Vector2.Zero, 1, SpriteEffects.None, 1);
            spriteBatch.End();
            base.Draw(gameTime); 


            // TODO: Add your drawing code here


        }
    }
}