GetExistingSystemManaged
Return an existing instance of a system of type T in this World.
Read time 3 minutesLast updated 13 hours ago
Definition
- Type: Method
- Namespace: Unity.Entities
- Assembly: UnityEngine.EntitiesModule
GetExistingSystemManaged<T>()
Return an existing instance of a system of type in this World.
Tpublic T GetExistingSystemManaged<T>() where T : ComponentSystemBase
Returns
Type | Description |
|---|---|
| T | The existing instance of system type |
Remarks
Note: This system reference is not guaranteed to be safe to use. If the system or world is destroyed then the OnDestroy and cleanup functionality will have been called for this system.
If possible, using World.GetExistingSystem is preferred, and instead of public member data, component data is recommended for system level data that needs to be shared between systems or externally to them. This defines a data protocol for the system which is separated from the system functionality.
Private member data which is only used internally to the system is recommended.
Keep in mind using a managed reference for systems
-
encourages coupling of data and functionality
-
couples data to the system type with no direct path to decouple
-
does not provide lifetime or thread safety guarantees for data access
-
does not provide lifetime or thread safety guarantees for system access through the returned managed reference
GetExistingSystemManaged(Type)
Return an existing instance of a system of type in this World. Prefer the version that takes a SystemTypeIndex where possible to avoid unnecessary reflection.
typepublic ComponentSystemBase GetExistingSystemManaged(Type type)
Parameters
The system type
Returns
Type | Description |
|---|---|
| ComponentSystemBase | The existing instance of system type |
Remarks
Note: This system reference is not guaranteed to be safe to use. If the system or world is destroyed then the OnDestroy and cleanup functionality will have been called for this system.
If possible, using World.GetExistingSystem is preferred, and instead of public member data, component data is recommended for system level data that needs to be shared between systems or externally to them. This defines a data protocol for the system which is separated from the system functionality.
Private member data which is only used internally to the system is recommended.
Keep in mind using a managed reference for systems
-
encourages coupling of data and functionality
-
couples data to the system type with no direct path to decouple
-
does not provide lifetime or thread safety guarantees for data access
-
does not provide lifetime or thread safety guarantees for system access through the returned managed reference
GetExistingSystemManaged(SystemTypeIndex)
Return an existing instance of a system of type in this World. This avoids unnecessary reflection.
typepublic ComponentSystemBase GetExistingSystemManaged(SystemTypeIndex type)
Parameters
The system type
Returns
Type | Description |
|---|---|
| ComponentSystemBase | The existing instance of system type |
Remarks
Note: This system reference is not guaranteed to be safe to use. If the system or world is destroyed then the OnDestroy and cleanup functionality will have been called for this system.
If possible, using World.GetExistingSystem is preferred, and instead of public member data, component data is recommended for system level data that needs to be shared between systems or externally to them. This defines a data protocol for the system which is separated from the system functionality.
Private member data which is only used internally to the system is recommended.
Keep in mind using a managed reference for systems
-
encourages coupling of data and functionality
-
couples data to the system type with no direct path to decouple
-
does not provide lifetime or thread safety guarantees for data access
-
does not provide lifetime or thread safety guarantees for system access through the returned managed reference