DefineNestedType Method (String, TypeAttributes, Type, PackingSize)

TypeBuilder.DefineNestedType Method (String, TypeAttributes, Type, PackingSize)

Defines a nested type, given its name, attributes, the type that it extends, and the packing size.

Namespace:  System.Reflection.Emit
Assembly:  mscorlib (in mscorlib.dll)

public TypeBuilder DefineNestedType(
	string name,
	TypeAttributes attr,
	Type parent,
	PackingSize packSize


Type: System.String

The short name of the type. name cannot contain embedded nulls.

Type: System.Reflection.TypeAttributes

The attributes of the type.

Type: System.Type

The type that the nested type extends.

Type: System.Reflection.Emit.PackingSize

The packing size of the type.

Return Value

Type: System.Reflection.Emit.TypeBuilder
The defined nested type.


The nested attribute is not specified.


This type is sealed.


This type is an array.


This type is an interface, but the nested type is not an interface.


The length of name is zero.


name is null.

This method can be used to create nested types even after the CreateType method has been called on the enclosing type.

The nested type needs to be complete before you can reflect on it using GetMembers, GetNestedType, or GetNestedTypes.

See the description of CreateType for the order in which nested types and nesting types should be completed.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

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