表示圆形的 2D 物理碰撞体。
另请参阅：BoxCollider 类、PolygonCollider2D 类。
| radius | 圆形的半径。 |
| enabled | 启用的 Behaviour 可更新，禁用的 Behaviour 不可更新。 |
| isActiveAndEnabled | Reports whether a GameObject and its associated Behaviour is active and enabled. |
| attachedRigidbody | 附加到 Collider2D 的 Rigidbody2D。 |
| bounciness | 获取碰撞体使用的弹力。 |
| bounds | 碰撞体的世界空间包围区域。 |
| callbackLayers | The Layers that this Collider2D will report collision or trigger callbacks for during a contact with another Collider2D. |
| composite | 获取可附加到该碰撞体的 CompositeCollider2D。 |
| compositeCapable | Indicates if this Collider2D is capable of being composited by the CompositeCollider2D. |
| compositeOperation | The composite operation to be used by a CompositeCollider2D. |
| compositeOrder | The composite operation order to be used when a CompositeCollider2D is used. |
| contactCaptureLayers | The layers of other Collider2D involved in contacts with this Collider2D that will be captured. |
| density | 碰撞体的密度，用于计算其质量（如果启用自动质量）。 |
| errorState | The error state that indicates the state of the physics shapes the 2D Collider tried to create. (Read Only) |
| excludeLayers | The additional Layers that this Collider2D should exclude when deciding if a contact with another Collider2D should happen or not. |
| forceReceiveLayers | The Layers that this Collider2D can receive forces from during a Collision contact with another Collider2D. |
| forceSendLayers | The Layers that this Collider2D is allowed to send forces to during a Collision contact with another Collider2D. |
| friction | 获取碰撞体使用的摩擦力。 |
| includeLayers | The additional Layers that this Collider2D should include when deciding if a contact with another Collider2D should happen or not. |
| isTrigger | 是否将碰撞体配置成了触发器？ |
| layerOverridePriority | A decision priority assigned to this Collider2D used when there is a conflicting decision on whether a contact between itself and another Collision2D should happen or not. |
| localToWorldMatrix | The transformation matrix used to transform the Collider physics shapes to world space. |
| offset | 碰撞体几何形状的局部偏移。 |
| shapeCount | The number of active PhysicsShape2D the Collider2D is currently using. |
| sharedMaterial | 应用于碰撞体的 PhysicsMaterial2D。 |
| usedByEffector | 附加的特效器是否使用该碰撞体。 |
| gameObject | 此组件附加到的游戏对象。始终将组件附加到游戏对象。 |
| tag | 此游戏对象的标签。 |
| transform | 附加到此 GameObject 的 Transform。 |
| hideFlags | 该对象应该隐藏、随场景一起保存还是由用户修改？ |
| name | 对象的名称。 |
| Cast | 将碰撞体形状投射到从该碰撞体位置开始的场景中，而忽略该碰撞体本身。 |
| ClosestPoint | 返回此碰撞体周边上最接近指定 position 的点。 |
| CreateMesh | 创建与 Collider2D 几何体定义的区域相同的平面 Mesh。 |
| Distance | 计算该碰撞体与另一个碰撞体的最小间距。 |
| GetContacts | 获取此碰撞体的所有接触点。 |
| GetShapeBounds | Retrieves a list of Bounds for all PhysicsShape2D created by this Collider2D, and returns the combined Bounds of the retrieved list. |
| GetShapeHash | 根据 Collider2D 的几何体生成简单哈希值。 |
| GetShapes | Gets all the PhysicsShape2D used by the Collider2D. |
| IsTouching | 检查该碰撞体是否正在接触 /collider/。 |
| IsTouchingLayers | 检查该碰撞体是否正在接触指定 layerMask 上的任何碰撞体。 |
| Overlap | 获取与该碰撞体重叠的所有碰撞体的列表。 |
| OverlapPoint | 检查碰撞体是否与空间中的某个点重叠。 |
| Raycast | 将光线投射到从碰撞体位置开始的场景中，并忽略碰撞体本身。 |
| BroadcastMessage | 调用此游戏对象或其任何子项中的每个 MonoBehaviour 上名为 methodName 的方法。 |
| CompareTag | Checks the GameObject's tag against the defined tag. |
| GetComponent | Gets a reference to a component of type T on the same GameObject as the component specified. |
| GetComponentInChildren | Gets a reference to a component of type T on the same GameObject as the component specified, or any child of the GameObject. |
| GetComponentInParent | Gets a reference to a component of type T on the same GameObject as the component specified, or any parent of the GameObject. |
| GetComponents | Gets references to all components of type T on the same GameObject as the component specified. |
| GetComponentsInChildren | Gets references to all components of type T on the same GameObject as the component specified, and any child of the GameObject. |
| GetComponentsInParent | Gets references to all components of type T on the same GameObject as the component specified, and any parent of the GameObject. |
| SendMessage | 调用此游戏对象中的每个 MonoBehaviour 上名为 methodName 的方法。 |
| SendMessageUpwards | 调用此游戏对象中的每个 MonoBehaviour 上或此行为的每个父级上名为 methodName 的方法。 |
| TryGetComponent | 获取指定类型的组件（如果存在）。 |
| GetInstanceID | Gets the instance ID of the object. |
| ToString | 返回对象的名称。 |
| Destroy | 移除 GameObject、组件或资源。 |
| DestroyImmediate | 立即销毁对象 /obj/。强烈建议您改用 Destroy。 |
| DontDestroyOnLoad | 在加载新的 Scene 时，请勿销毁 Object。 |
| FindAnyObjectByType | Retrieves any active loaded object of Type type. |
| FindFirstObjectByType | Retrieves the first active loaded object of Type type. |
| FindObjectsByType | Retrieves a list of all loaded objects of Type type. |
| Instantiate | 克隆 original 对象并返回克隆对象。 |
| bool | 该对象是否存在？ |
| operator != | 比较两个对象是否引用不同的对象。 |
| operator == | 比较两个对象引用，判断它们是否引用同一个对象。 |
| OnCollisionEnter2D | 当传入碰撞体与该对象的碰撞体接触时发送（仅限 2D 物理）。 |
| OnCollisionExit2D | 当另一个对象上的碰撞体停止接触该对象的碰撞体时发送（仅限 2D 物理）。 |
| OnCollisionStay2D | 在另一个对象上的碰撞体正在接触该对象的碰撞体时发送每个帧（仅限 2D 物理）。 |
| OnTriggerEnter2D | 当另一个对象进入附加到该对象的触发碰撞体时发送（仅限 2D 物理）。 |
| OnTriggerExit2D | 当另一个对象离开附加到该对象的触发碰撞体时发送（仅限 2D 物理）。 |
| OnTriggerStay2D | 在另一个对象位于附加到该对象的触发碰撞体之内时发送每个帧（仅限 2D 物理）。 |