# RunBeforeAssemblyAttribute

> Add this attribute to a callback method to indicate that this callback must be run before any callbacks that are part of the specified assembly.

## Definition

* **Type:** Class
* **Namespace:** [UnityEditor.Callbacks](/engine/6000.0/script-reference/unityeditor/callbacks.md)
* **Assembly:** UnityEditor
* **Inherits from:** [Attribute](https://learn.microsoft.com/dotnet/api/system.attribute)
* **Implements:** [\_Attribute](https://learn.microsoft.com/dotnet/api/system.runtime.interopservices._attribute)

```csharp
[AttributeUsage(AttributeTargets.Method, AllowMultiple = true)]
public class RunBeforeAssemblyAttribute : Attribute, _Attribute
```

## Remarks

To define dependencies for a callback, use the following attributes:

* [RunAfterClassAttribute](/engine/6000.0/script-reference/unityeditor/callbacks/runafterclassattribute.md), [RunBeforeClassAttribute](/engine/6000.0/script-reference/unityeditor/callbacks/runbeforeclassattribute.md)
* [RunAfterAssemblyAttribute](/engine/6000.0/script-reference/unityeditor/callbacks/runafterassemblyattribute.md), [RunBeforeAssemblyAttribute](/engine/6000.0/script-reference/unityeditor/callbacks/runbeforeassemblyattribute.md)
* [RunAfterPackageAttribute](/engine/6000.0/script-reference/unityeditor/callbacks/runafterpackageattribute.md), [RunBeforePackageAttribute](/engine/6000.0/script-reference/unityeditor/callbacks/runbeforepackageattribute.md)

When the callback is invoked, Unity generates a dependency graph and uses topological sorting to ensure that all dependencies are run in sequence based on their dependencies. If callbacks dependencies are not present in the project then the instruction will be ignored during the generation of the dependency graph.

**Note:** Defining callback dependencies is currently only supported by the [AssetPostprocessor.OnPostprocessAllAssets(string\[\], string\[\], string\[\], string\[\], bool)](/engine/6000.0/script-reference/unityeditor/assetpostprocessor/onpostprocessallassets.md) callback.

## Examples

```csharp
using UnityEditor;
using UnityEditor.Callbacks;
using UnityEngine;

// This example shows how to ensure that a callback is called before the Addressables assembly has been called.
class MyPostprocessor : AssetPostprocessor
{
    [RunBeforeAssembly("Unity.Addressables.Editor")]
    static void OnPostprocessAllAssets(string[] importedAssets, string[] deletedAssets, string[] movedAssets, string[] movedFromAssetPaths)
    {
        Debug.Log("MyAllPostprocessor");
    }
}
```

## Constructors

| Constructor                                                                                                                           | Description                                                                                                                                      |
| ------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------ |
| [RunBeforeAssemblyAttribute(System.String)](/engine/6000.0/script-reference/unityeditor/callbacks/runbeforeassemblyattribute/ctor.md) | Add this attribute to a callback method to indicate that this callback must be run before any callbacks that are part of the specified assembly. |

## Properties

| Property                                                                                                         | Description                                                         |
| ---------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
| [assemblyName](/engine/6000.0/script-reference/unityeditor/callbacks/runbeforeassemblyattribute/assemblyname.md) | The name of the assembly that should be called after this callback. |

## Inheritance

**Inherited Members:**

* [Attribute.GetCustomAttributes(MemberInfo, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-memberinfo-system-type\))
* [Attribute.GetCustomAttributes(MemberInfo, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-memberinfo-system-type-system-boolean\))
* [Attribute.GetCustomAttributes(MemberInfo)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-memberinfo\))
* [Attribute.GetCustomAttributes(MemberInfo, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-memberinfo-system-boolean\))
* [Attribute.IsDefined(MemberInfo, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.isdefined#system-attribute-isdefined\(system-reflection-memberinfo-system-type\))
* [Attribute.IsDefined(MemberInfo, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.isdefined#system-attribute-isdefined\(system-reflection-memberinfo-system-type-system-boolean\))
* [Attribute.GetCustomAttribute(MemberInfo, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattribute#system-attribute-getcustomattribute\(system-reflection-memberinfo-system-type\))
* [Attribute.GetCustomAttribute(MemberInfo, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattribute#system-attribute-getcustomattribute\(system-reflection-memberinfo-system-type-system-boolean\))
* [Attribute.GetCustomAttributes(ParameterInfo)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-parameterinfo\))
* [Attribute.GetCustomAttributes(ParameterInfo, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-parameterinfo-system-type\))
* [Attribute.GetCustomAttributes(ParameterInfo, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-parameterinfo-system-type-system-boolean\))
* [Attribute.GetCustomAttributes(ParameterInfo, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-parameterinfo-system-boolean\))
* [Attribute.IsDefined(ParameterInfo, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.isdefined#system-attribute-isdefined\(system-reflection-parameterinfo-system-type\))
* [Attribute.IsDefined(ParameterInfo, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.isdefined#system-attribute-isdefined\(system-reflection-parameterinfo-system-type-system-boolean\))
* [Attribute.GetCustomAttribute(ParameterInfo, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattribute#system-attribute-getcustomattribute\(system-reflection-parameterinfo-system-type\))
* [Attribute.GetCustomAttribute(ParameterInfo, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattribute#system-attribute-getcustomattribute\(system-reflection-parameterinfo-system-type-system-boolean\))
* [Attribute.GetCustomAttributes(Module, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-module-system-type\))
* [Attribute.GetCustomAttributes(Module)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-module\))
* [Attribute.GetCustomAttributes(Module, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-module-system-boolean\))
* [Attribute.GetCustomAttributes(Module, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-module-system-type-system-boolean\))
* [Attribute.IsDefined(Module, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.isdefined#system-attribute-isdefined\(system-reflection-module-system-type\))
* [Attribute.IsDefined(Module, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.isdefined#system-attribute-isdefined\(system-reflection-module-system-type-system-boolean\))
* [Attribute.GetCustomAttribute(Module, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattribute#system-attribute-getcustomattribute\(system-reflection-module-system-type\))
* [Attribute.GetCustomAttribute(Module, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattribute#system-attribute-getcustomattribute\(system-reflection-module-system-type-system-boolean\))
* [Attribute.GetCustomAttributes(Assembly, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-assembly-system-type\))
* [Attribute.GetCustomAttributes(Assembly, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-assembly-system-type-system-boolean\))
* [Attribute.GetCustomAttributes(Assembly)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-assembly\))
* [Attribute.GetCustomAttributes(Assembly, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattributes#system-attribute-getcustomattributes\(system-reflection-assembly-system-boolean\))
* [Attribute.IsDefined(Assembly, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.isdefined#system-attribute-isdefined\(system-reflection-assembly-system-type\))
* [Attribute.IsDefined(Assembly, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.isdefined#system-attribute-isdefined\(system-reflection-assembly-system-type-system-boolean\))
* [Attribute.GetCustomAttribute(Assembly, Type)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattribute#system-attribute-getcustomattribute\(system-reflection-assembly-system-type\))
* [Attribute.GetCustomAttribute(Assembly, Type, bool)](https://learn.microsoft.com/dotnet/api/system.attribute.getcustomattribute#system-attribute-getcustomattribute\(system-reflection-assembly-system-type-system-boolean\))
* [Attribute.Equals(Object)](https://learn.microsoft.com/dotnet/api/system.attribute.equals)
* [Attribute.GetHashCode()](https://learn.microsoft.com/dotnet/api/system.attribute.gethashcode)
* [Attribute.Match(Object)](https://learn.microsoft.com/dotnet/api/system.attribute.match)
* [Attribute.IsDefaultAttribute()](https://learn.microsoft.com/dotnet/api/system.attribute.isdefaultattribute)
* [Attribute.TypeId()](https://learn.microsoft.com/dotnet/api/system.attribute.typeid)