# GetAllSystems(WorldSystemFilterFlags, bool)

> Calculates a list of all systems filtered with WorldSystemFilterFlags, [DisableAutoCreation] etc. Prefer GetAllSystemTypeIndices where possible to avoid extra reflection.

## Definition

* **Type:** Method
* **Namespace:** [Unity.Entities](/engine/7000.0/script-reference/unity/entities.md)
* **Assembly:** UnityEngine.EntitiesModule

```csharp
public static IReadOnlyList<Type> GetAllSystems(WorldSystemFilterFlags filterFlags, bool requireExecuteInEditor = false)
```

### Parameters

**** (\[WorldSystemFilterFlags]\(/engine/7000.0/script-reference/unity/entities/worldsystemfilterflags)): The filter flags to search for.**** (\[bool]\(https\://learn.microsoft.com/dotnet/api/system.boolean)): Optionally require that \[WorldSystemFilter(WorldSystemFilterFlags.Editor)] is present on the system. This is used when creating edit mode worlds.

### Returns

| Type                                                                                                      | Description                  |
| --------------------------------------------------------------------------------------------------------- | ---------------------------- |
| [IReadOnlyList\<Type>](https://learn.microsoft.com/dotnet/api/system.collections.generic.ireadonlylist-1) | The list of filtered systems |