--- title: OnAssemblyLoadedAttribute product: Unity Editor version: '7000.0' latest_version: '7000.0' status: current canonical: https://docs.unity.com/en-us/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/onassemblyloadedattribute latest_url: https://docs.unity.com/en-us/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/onassemblyloadedattribute.md last_updated: 2026-10-20 generated_at: 2026-11-03T23:01:36.698Z locale: en-us --- # OnAssemblyLoadedAttribute > Marks a static method as a callback that Unity invokes after Unity loads each assembly. ## Definition * **Type:** Class * **Namespace:** [Unity.Scripting.LifecycleManagement](/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement.md) * **Assembly:** Unity.Scripting * **Inherits from:** [LifecycleAttributeBase](/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/lifecycleattributebase.md) ```csharp [AttributeUsage(AttributeTargets.Method, AllowMultiple = false)] public sealed class OnAssemblyLoadedAttribute : LifecycleAttributeBase ``` ## Remarks Unity invokes these methods for each assembly in dependency order, so an assembly's dependencies are processed first, and before [OnCodeLoadedAttribute](/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/oncodeloadedattribute.md) callbacks run. Use this callback for setup or teardown that applies to one assembly. For work that needs every assembly to be loaded, use [OnCodeLoadedAttribute](/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/oncodeloadedattribute.md) and [OnCodeUnloadingAttribute](/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/oncodeunloadingattribute.md) instead. This is a method attribute that can only be applied to `static` methods with no parameters and return type `void`. Additional Resources: [OnCodeLoadedAttribute](/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/oncodeloadedattribute.md), [OnCodeUnloadingAttribute](/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/oncodeunloadingattribute.md). ## Constructors | Constructor | Description | | ------------------------------------------------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------- | | [OnAssemblyLoadedAttribute()](/engine/7000.0/script-reference/unity/scripting/lifecyclemanagement/onassemblyloadedattribute/ctor.md) | Marks the decorated static method to be invoked after the containing assembly has been loaded. | ## 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)