Error in playerindex

我正试图将我的游戏从XNA移植到SharpDX，但我找不到解决我的问题的方法:

namespace TomShane.Neoforce.Central
{       
    public class InputState
    {
        #region Fields
        public const int MaxInputs = 4;
        public readonly KeyboardState[] CurrentKeyboardStates;
     //   public readonly GamePadState[] CurrentGamePadStates;
        public readonly KeyboardState[] LastKeyboardStates;
   //     public readonly GamePadState[] LastGamePadStates;
        public readonly KeyboardManager Keyboard;
      //  public readonly bool[] GamePadWasConnected;
       // public TouchCollection TouchState;
        //public readonly List<GestureSample> Gestures = new List<GestureSample>();
        #endregion
        #region Initialization

        /// <summary>
        /// Constructs a new input state.
        /// </summary>
        public InputState()
        {
            CurrentKeyboardStates = new KeyboardState[MaxInputs];
        //    CurrentGamePadStates = new GamePadState[MaxInputs];
            LastKeyboardStates = new KeyboardState[MaxInputs];
          //  LastGamePadStates = new GamePadState[MaxInputs];
            //GamePadWasConnected = new bool[MaxInputs];
        }

        #endregion
        #region Public Methods

        /// <summary>
        /// Reads the latest state of the keyboard and gamepad.
        /// </summary>
        public void Update()
        {
            for (int i = 0; i < MaxInputs; i++)
            {
                LastKeyboardStates[i] = CurrentKeyboardStates[i];
         //       LastGamePadStates[i] = CurrentGamePadStates[i];
                CurrentKeyboardStates[i] = Keyboard.GetState();
//                CurrentGamePadStates[i] = GamePad.GetState((PlayerIndex)i);
                // Keep track of whether a gamepad has ever been
                // connected, so we can detect if it is unplugged.
                //if (CurrentGamePadStates[i].IsConnected)
                //{
                //    GamePadWasConnected[i] = true;
                //}
            }
         //   TouchState = TouchPanel.GetState();
            //Gestures.Clear();
            //while (TouchPanel.IsGestureAvailable)
            //{
            //    Gestures.Add(TouchPanel.ReadGesture());
            //}
        }

        /// <summary>
        /// Helper for checking if a key was newly pressed during this update. The
        /// controllingPlayer parameter specifies which player to read input for.
        /// If this is null, it will accept input from any player. When a keypress
        /// is detected, the output playerIndex reports which player pressed it.
        /// </summary>
        public bool IsNewKeyPress(Keys key, PlayerIndex? controllingPlayer,
                                            out PlayerIndex playerIndex)
        {
            if (controllingPlayer.HasValue)
            {
                // Read input from the specified player.
                playerIndex = controllingPlayer.Value;
              int i = (int)playerIndex;
               // int i = playerIndex;
                return (CurrentKeyboardStates[i].IsKeyDown(key) &&
                        LastKeyboardStates[i].IsKeyPressed(key));
                        //IsKeyUp(key));
            }
            else
            {
                // Accept input from any player.
                return (IsNewKeyPress(key, PlayerIndex.One, out playerIndex)); //||
                       // IsNewKeyPress(key, PlayerIndex.Two, out playerIndex) ||
                      //  IsNewKeyPress(key, PlayerIndex.Three, out playerIndex) ||
                       // IsNewKeyPress(key, PlayerIndex.Four, out playerIndex));
            }
        }

        /// <summary>
        /// Helper for checking if a button was newly pressed during this update.
        /// The controllingPlayer parameter specifies which player to read input for.
        /// If this is null, it will accept input from any player. When a button press
        /// is detected, the output playerIndex reports which player pressed it.
        /// </summary>

        /// <summary>
        /// Checks for a "menu select" input action.
        /// The controllingPlayer parameter specifies which player to read input for.
        /// If this is null, it will accept input from any player. When the action
        /// is detected, the output playerIndex reports which player pressed it.
        /// </summary>
        public bool IsMenuSelect(PlayerIndex? controllingPlayer,
                                 out PlayerIndex playerIndex)
        {
            return IsNewKeyPress(Keys.Space, controllingPlayer, out playerIndex) ||
                   IsNewKeyPress(Keys.Enter, controllingPlayer, out playerIndex);
        }

        /// <summary>
        /// Checks for a "menu cancel" input action.
        /// The controllingPlayer parameter specifies which player to read input for.
        /// If this is null, it will accept input from any player. When the action
        /// is detected, the output playerIndex reports which player pressed it.
        /// </summary>
        public bool IsMenuCancel(PlayerIndex? controllingPlayer,
                                 out PlayerIndex playerIndex)
        {
            return IsNewKeyPress(Keys.Escape, controllingPlayer, out playerIndex); 
        }

        /// <summary>
        /// Checks for a "menu up" input action.
        /// The controllingPlayer parameter specifies which player to read
        /// input for. If this is null, it will accept input from any player.
        /// </summary>
       public bool IsMenuUp(PlayerIndex? controllingPlayer)
        {
            PlayerIndex playerIndex;
            return IsNewKeyPress(Keys.Up, controllingPlayer, out playerIndex);
        }

        /// <summary>
        /// Checks for a "menu down" input action.
        /// The controllingPlayer parameter specifies which player to read
        /// input for. If this is null, it will accept input from any player.
        /// </summary>
        public bool IsMenuDown(PlayerIndex? controllingPlayer)
        {
            PlayerIndex playerIndex;
            return IsNewKeyPress(Keys.Down, controllingPlayer, out playerIndex);// ||
                 //  IsNewButtonPress(Buttons.DPadDown, controllingPlayer, out playerIndex) ||
                  // IsNewButtonPress(Buttons.LeftThumbstickDown, controllingPlayer, out playerIndex);
        }

        /// <summary>
        /// Checks for a "pause the game" input action.
        /// The controllingPlayer parameter specifies which player to read
        /// input for. If this is null, it will accept input from any player.
        /// </summary>
        public bool IsPauseGame(PlayerIndex? controllingPlayer)
        {
            PlayerIndex playerIndex;
            return IsNewKeyPress(Keys.Escape, controllingPlayer, out playerIndex);// ||
                //   IsNewButtonPress(Buttons.Back, controllingPlayer, out playerIndex) ||
                  // IsNewButtonPress(Buttons.Start, controllingPlayer, out playerIndex);
        }

        #endregion
    }         
}

我得到这个错误。我不知道怎么修理它。

错误2"SharpDX"类型。PlayerIndex'必须是一个非空值类型，以便在泛型类型或方法'System中将其用作参数'T'。c:' users ' droo ' dropbox ' games' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 95 21 Central错误3:输入"SharpDX"。PlayerIndex'必须是一个非空值类型，以便在泛型类型或方法'System中将其用作参数'T'。' users ' droo ' dropbox ' games' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 156 21 Central错误4:输入"SharpDX"。PlayerIndex'必须是一个非空值类型，以便在泛型类型或方法'System中将其用作参数'T'。c:' users ' droo ' dropbox ' games' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 172 21 Central错误5:输入"SharpDX"。PlayerIndex'必须是一个非空值类型，以便在泛型类型或方法'System中将其用作参数'T'。' users ' droo ' dropbox ' games' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 186 20 Central错误6:输入"SharpDX"。PlayerIndex'必须是一个非空值类型，以便在泛型类型或方法'System中将其用作参数'T'。c:' users ' droo ' dropbox ' games' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 201 21 Central错误7输入"SharpDX"。PlayerIndex'必须是一个非空值类型，以便在泛型类型或方法'System中将其用作参数'T'。c:' users ' droo ' dropbox ' games' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 216 21 Central错误8无法转换类型"SharpDX"。' users ' droo ' dropbox ' games' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 103 23 Central在控制离开当前方法之前，必须将输出参数"playerIndex"分配给C:'Users'Pedro'Dropbox'GAMES' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 159错误10:在控制离开当前方法之前，必须将输出参数"playerIndex"分配给C:'Users'Pedro'Dropbox'GAMES' neoforceccontrols - sharpdx -master'Central'ScreenManager'InputState.cs 175 13 Central