TypeBuilder::DefineNestedType Method (String^, TypeAttributes, Type^, array<Type^>^)


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Defines a nested type, given its name, attributes, the type that it extends, and the interfaces that it implements.

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

TypeBuilder^ DefineNestedType(
	String^ name,
	TypeAttributes attr,
	Type^ parent,
	array<Type^>^ interfaces


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: array<System::Type^>^

The interfaces that the nested type implements.

Return Value

Type: System.Reflection.Emit::TypeBuilder^

The defined nested type.

Exception Condition

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 or greater than 1023.


This operation would create a type with a duplicate FullName in the current assembly.


name is null.


An element of the interfaces array 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.

A duplicate name is not necessarily created if name is identical to the name of a previously defined type or nested type. To be duplicates, the full names must be the same, including the namespace and all nesting types.

.NET Framework
Available since 1.1
Available since 2.0
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