一种可放置 Canvas 的元素，可用于修改子 Alpha、Raycasting、Enabled 状态。
画布组可用于修改子元素的状态。
An example of this would be a window which fades in over time, by modifying the alpha value of the group the children elements will be affected. The result alpha will be the multiplied result of any nested groups, multiplied with the canvas elements alpha.
You can configure Canvas Groups to not block raycasts. When you configure a Canvas Group to not block raycasts, graphic raycasting ignores anything in the group.
Let's say you have a Canvas GameObject with a CanvasGroup component on it, and you set the CanvasGroup component's alpha to 0. In that case, the Canvas does not render any of its child GameObjects.
Now suppose that the Canvas also has a child CanvasGroup GameObject that you do want to render. If you enable IgnoreParentGroups for the CanvasGroup GameObject, the parent Canvas does not render any of its child GameObjects, including the CanvasGroup you want to render.
To get the child CanvasGroup GameObject, do one of two things:
In the parent Canvas, set the CanvasGroup component's alpha to a small, non-zero value.
Add a Canvas component to the child CanvasGroup GameObject that you want to render.
| alpha | 设置组的 Alpha。 |
| blocksRaycasts | 该组是否阻止射线投射（允许碰撞）。 |
| ignoreParentGroups | 该组是否应忽略父组？ |
| interactable | 该组是否可交互（组下的元素是否处于启用状态）。 |
| IsRaycastLocationValid | 如果组允许射线投射，则返回 true。 |
| 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. |
| 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。 |
| 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。 |