我是一名C++程序员,尝试c#。我在C++中用box2d做了很多,但这是我第一次用c#。所以,我试图用更简单的物理引擎做一个简单的游戏。当我尝试编译我的代码(我正在使用visual studio c#2010 express和xna game studio 4.0)时,它在body.cs中停止在IBroadPhase broadPhase = World.ContactManager.BroadPhase;
出现此错误:nullreferenceexception was unhandled
。我相信这个问题是在我的播放器类,所以这里的该代码:“nullreferenceexception was unhandled”在较早的物理引擎body.cs中
public class Player : Entity
{
Vector2 position;
SpriteBatch spriteBatch;
Texture2D texture;
Rectangle rectangle;
Body body;
CircleShape shape;
Fixture fixture;
public Player()
{
// TODO: Construct any child components here
}
///
/// Allows the game component to perform any initialization it needs to before starting
/// to run. This is where it can query for any required services and load content.
///
public override void Initialize(World world, SpriteBatch spriteBatch, Texture2D texture)
{
// TODO: Add your initialization code here
this.spriteBatch = spriteBatch;
this.texture = texture;
rectangle = new Rectangle(0, 0, 11, 14);
body = BodyFactory.CreateBody(world);
body.BodyType = BodyType.Dynamic;
body.Position = new Vector2(0, 0);
shape = new CircleShape(1.0f, 1.0f);
fixture = body.CreateFixture(shape);
base.Initialize(world, spriteBatch, texture);
}
///
/// Allows the game component to update itself.
///
/// <param name="gameTime" />Provides a snapshot of timing values.
public override void Update(GameTime gameTime)
{
// TODO: Add your update code here
base.Update(gameTime);
}
public override void Draw(GameTime gameTime)
{
spriteBatch.Begin();
spriteBatch.Draw(texture, new Vector2(body.WorldCenter.X * 10, body.WorldCenter.Y * 10), rectangle, Color.White);
spriteBatch.End();
base.Draw(gameTime);
}
}
的预言者测试平台运行正常,所以我敢肯定我的代码的问题,而不是先知。如果您需要查看更多我的代码,请告诉我。我也在更早的论坛上发布了这个,所以如果我在那里得到答案,我会让你们知道。提前致谢。
我们可以有完整的堆栈跟踪吗? – user7116
请参阅:http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-in-net –
你还没有发布你说错误的代码行。无论如何,在该行放置一个断点并调试您的代码。当它到达断点时,将鼠标悬停在对象上并查看哪一个为空。当你试图访问一个null对象的成员时,你会得到这个异常。找到null并修复它。 –