我正在创建一个游戏，目前我有 3 个类，greenpaddle、ball 和 Game1。
当我运行我的游戏时，调试器跳到我spriteBatch.Begin();
并说NullReferenceException Unhandled。这是我的 Game1.cs：
public class Game1 : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
Ball ball;
GreenPaddle gPaddle;
Texture2D BackGround;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
graphics.PreferredBackBufferHeight = 500;
}
protected override void Initialize()
{
gPaddle = new GreenPaddle();
ball = new Ball(gPaddle);
}
/// <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);
BackGround = Content.Load<Texture2D>("pongBG");
gPaddle.LoadContent(Content);
ball.LoadContent(Content);
}
/// <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();
gPaddle.Update(gameTime);//Error Line
ball.Update(gameTime);
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.CornflowerBlue);
spriteBatch.Begin();//Error Line
spriteBatch.Draw(BackGround, new Vector2(0f, 0f), Color.White);
gPaddle.Draw(spriteBatch);
ball.Draw(spriteBatch);
spriteBatch.End();
base.Draw(gameTime);
}
}
不知道怎么回事，我从来没有遇到过这种情况。