Type.GetNestedTypes Method

Definition

Namespace:

System

Assembly:

System.Runtime.dll

Gets the types nested within the current Type.

Overloads

GetNestedTypes()	Returns the public types nested in the current Type.
GetNestedTypes(BindingFlags)	When overridden in a derived class, searches for the types nested in the current Type, using the specified binding constraints.

GetNestedTypes()

Source:

Type.cs

Returns the public types nested in the current Type.

public:
 cli::array <Type ^> ^ GetNestedTypes();

public Type[] GetNestedTypes ();

member this.GetNestedTypes : unit -> Type[]

Public Function GetNestedTypes () As Type()

Returns

Type[]

An array of Type objects representing the public types nested in the current Type (the search is not recursive), or an empty array of type Type if no public types are nested in the current Type.

Examples

The following example defines a nested class and a struct in MyClass, and then obtains objects of the nested types using the type of MyClass.

using namespace System;
using namespace System::Reflection;
public ref class MyClass
{
public:
   ref class NestClass
   {
      public:
         static int myPublicInt = 0;
   };

   ref struct NestStruct
   {
      public:
         static int myPublicInt = 0;
   };
};

int main()
{
   try
   {
      // Get the Type object corresponding to MyClass.
      Type^ myType = MyClass::typeid;
      
      // Get an array of nested type objects in MyClass.
      array<Type^>^nestType = myType->GetNestedTypes();
      Console::WriteLine( "The number of nested types is {0}.", nestType->Length );
      System::Collections::IEnumerator^ myEnum = nestType->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         Type^ t = safe_cast<Type^>(myEnum->Current);
         Console::WriteLine( "Nested type is {0}.", t );
      }
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "Error {0}", e->Message );
   }
}

using System;
using System.Reflection;
public class MyClass
{
    public class NestClass
    {
        public static int myPublicInt=0;
    }
    public struct NestStruct
    {
        public static int myPublicInt=0;
    }
}

public class MyMainClass
{
    public static void Main()
    {
        try
        {
            // Get the Type object corresponding to MyClass.
            Type myType=typeof(MyClass);
            // Get an array of nested type objects in MyClass.
            Type[] nestType=myType.GetNestedTypes();
            Console.WriteLine("The number of nested types is {0}.", nestType.Length);
            foreach(Type t in nestType)
                Console.WriteLine("Nested type is {0}.", t.ToString());
        }
        catch(Exception e)
        {
            Console.WriteLine("Error"+e.Message);
        }
    }
}

Imports System.Reflection

Public Class MyClass1
    Public Class NestClass
        Public Shared myPublicInt As Integer = 0
    End Class

    Public Structure NestStruct
        Public myPublicInt As Integer
    End Structure 'NestStruct
End Class

Public Class MyMainClass
    Public Shared Sub Main()
        Try
            ' Get the Type object corresponding to MyClass.
            Dim myType As Type = GetType(MyClass1)
            ' Get an array of nested type objects in MyClass.                 
            Dim nestType As Type() = myType.GetNestedTypes()
            Console.WriteLine("The number of nested types is {0}.", nestType.Length)
            Dim t As Type
            For Each t In nestType
                Console.WriteLine("Nested type is {0}.", t.ToString())
            Next t
        Catch e As Exception
            Console.WriteLine("Error", e.Message.ToString())
        End Try
    End Sub
End Class

Remarks

In .NET 6 and earlier versions, the GetNestedTypes method does not return types in a particular order, such as alphabetical or declaration order. Your code must not depend on the order in which types are returned, because that order varies. However, starting with .NET 7, the ordering is deterministic based upon the metadata ordering in the assembly.

Only the public types immediately nested in the current type are returned; the search is not recursive.

The following table shows what members of a base class are returned by the Get methods when reflecting on a type.

Member Type	Static	Non-Static
Constructor	No	No
Field	No	Yes. A field is always hide-by-name-and-signature.
Event	Not applicable	The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.
Method	No	Yes. A method (both virtual and non-virtual) can be hide-by-name or hide-by-name-and-signature.
Nested Type	No	No
Property	Not applicable	The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.

1. Hide-by-name-and-signature considers all of the parts of the signature, including custom modifiers, return types, parameter types, sentinels, and unmanaged calling conventions. This is a binary comparison.

2. For reflection, properties and events are hide-by-name-and-signature. If you have a property with both a get and a set accessor in the base class, but the derived class has only a get accessor, the derived class property hides the base class property, and you will not be able to access the setter on the base class.

3. Custom attributes are not part of the common type system.

If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the nested types of the class constraint.

If a nested type is generic, this method returns its generic type definition. This is true even if the enclosing generic type is a closed constructed type.

Note

If the current Type represents a generic type defined in C#, Visual Basic, or C++, its nested types are all generic even if they have no generic parameters of their own. This is not necessarily true of nested types defined in dynamic assemblies or compiled with the Ilasm.exe (IL Assembler).

For information on nested generic types, and on constructing nested generic types from their generic type definitions, see MakeGenericType.

See also

• GetNestedType(String)

GetNestedTypes(BindingFlags)

Source:

Type.cs

When overridden in a derived class, searches for the types nested in the current Type, using the specified binding constraints.

public:
 abstract cli::array <Type ^> ^ GetNestedTypes(System::Reflection::BindingFlags bindingAttr);

public abstract Type[] GetNestedTypes (System.Reflection.BindingFlags bindingAttr);

abstract member GetNestedTypes : System.Reflection.BindingFlags -> Type[]

Public MustOverride Function GetNestedTypes (bindingAttr As BindingFlags) As Type()

Parameters

bindingAttr

BindingFlags

A bitwise combination of the enumeration values that specify how the search is conducted.

-or-

Default to return null.

Returns

Type[]

An array of Type objects representing all the types nested in the current Type that match the specified binding constraints (the search is not recursive), or an empty array of type Type, if no nested types are found that match the binding constraints.

Examples

The following example creates two nested public classes and two nested protected classes, and displays information for classes that match the specified binding constraints.

using namespace System;
using namespace System::Reflection;

// Create a class with two nested public classes and two nested protected classes.
public ref class MyTypeClass
{
   public:
      ref class Myclass1{};
   
   public:
      ref class Myclass2{};
   
   protected:
      ref class MyClass3{};
   
   protected:
      ref class MyClass4{};
};

void DisplayTypeInfo(array<Type^>^ myArrayType)
{
   // Display the information for all the nested classes.
   for each (Type^ t in myArrayType)
      Console::WriteLine( "The name of the nested class is {0}.", t->FullName);
}

int main()
{
   Type^ myType = MyTypeClass::typeid;
   
   // Get the public nested classes.
   array<Type^>^myTypeArray = myType->GetNestedTypes( static_cast<BindingFlags>(BindingFlags::Public));
   Console::WriteLine( "The number of nested public classes is {0}.", myTypeArray->Length );
  
   // Display all the public nested classes.
   DisplayTypeInfo( myTypeArray );
   Console::WriteLine();
   
   // Get the nonpublic nested classes.
   array<Type^>^myTypeArray1 = myType->GetNestedTypes( static_cast<BindingFlags>(BindingFlags::NonPublic));
   Console::WriteLine( "The number of nested protected classes is {0}.", myTypeArray1->Length );
   
   // Display all the nonpublic nested classes.
   DisplayTypeInfo( myTypeArray1 );
}
// The example displays the following output:
//       The number of public nested classes is 2.
//       The name of the nested class is MyTypeClass+Myclass1.
//       The name of the nested class is MyTypeClass+Myclass2.
//       
//       The number of protected nested classes is 2.
//       The name of the nested class is MyTypeClass+MyClass3.
//       The name of the nested class is MyTypeClass+MyClass4.

using System;
using System.Reflection;

// Create a class with 2 nested public and 2 nested protected classes.
public class MyTypeClass
{
    public class Myclass1
    {
    }

    public class Myclass2
    {
    }

    protected class MyClass3
    {
    }

    protected class MyClass4
    {
    }
}

public class TypeMain
{
    public static void Main()
    {
        Type myType = (typeof(MyTypeClass));
        // Get the public nested classes.
        Type[] myTypeArray = myType.GetNestedTypes(BindingFlags.Public);
        Console.WriteLine("The number of nested public classes is {0}.", myTypeArray.Length);
        // Display all the public nested classes.
        DisplayTypeInfo(myTypeArray);
        Console.WriteLine();

        // Get the nonpublic nested classes.
        Type[] myTypeArray1 = myType.GetNestedTypes(BindingFlags.NonPublic|BindingFlags.Instance);
        Console.WriteLine("The number of nested protected classes is {0}.", myTypeArray1.Length);
        // Display all the nonpublic nested classes.
        DisplayTypeInfo(myTypeArray1);		
    }

    public static void DisplayTypeInfo(Type[] myArrayType)
    {
        // Display the information for all the nested classes.
        foreach (var t in myArrayType)
            Console.WriteLine("The name of the nested class is {0}.", t.FullName);
    }
}
// The example displays the following output:
//       The number of public nested classes is 2.
//       The name of the nested class is MyTypeClass+Myclass1.
//       The name of the nested class is MyTypeClass+Myclass2.
//
//       The number of protected nested classes is 2.
//       The name of the nested class is MyTypeClass+MyClass3.
//       The name of the nested class is MyTypeClass+MyClass4.

Imports System.Reflection

' Create a class with three properties.
Public Class MyTypeClass
    Public Class Myclass1
    End Class 

    Public Class Myclass2
    End Class 

    Protected Class MyClass3
    End Class 

    Protected Class MyClass4
    End Class 
End Class 

Public Class TypeMain
    Public Shared Sub Main()
        Dim myType As Type = GetType(MyTypeClass)

        ' Get the public nested classes.
        Dim myTypeArray As Type() = myType.GetNestedTypes((BindingFlags.Public))
        Console.WriteLine("The number of public nested classes is {0}.", myTypeArray.Length.ToString())
        ' Display all the public nested classes.
        DisplayTypeInfo(myTypeArray)
        Console.WriteLine()
        
        ' Get the nonpublic nested classes.
        Dim myTypeArray1 As Type() = myType.GetNestedTypes((BindingFlags.NonPublic))
        Console.WriteLine("The number of protected nested classes is {0}.", myTypeArray1.Length.ToString())
        ' Display  the information for all nested classes.
        DisplayTypeInfo(myTypeArray1)
    End Sub 

    Public Shared Sub DisplayTypeInfo(ByVal myArrayType() As Type)
        ' Display the information for all nested classes.
        For Each t In myArrayType
            Console.WriteLine("The name of the nested class is {0}.", t.FullName)
        Next 
    End Sub 
End Class  
' The example displays the following output:
'       The number of public nested classes is 2.
'       The name of the nested class is MyTypeClass+Myclass1.
'       The name of the nested class is MyTypeClass+Myclass2.
'       
'       The number of protected nested classes is 2.
'       The name of the nested class is MyTypeClass+MyClass3.
'       The name of the nested class is MyTypeClass+MyClass4.

Remarks

The search for nested types is not recursive.

In .NET 6 and earlier versions, the GetNestedTypes method does not return types in a particular order, such as alphabetical or declaration order. Your code must not depend on the order in which types are returned, because that order varies. However, starting with .NET 7, the ordering is deterministic based upon the metadata ordering in the assembly.

The following BindingFlags filter flags can be used to define which nested types to include in the search:

• You must specify either BindingFlags.Public or BindingFlags.NonPublic to get a return.

• Specify BindingFlags.Public to include public nested types in the search.

• Specify BindingFlags.NonPublic to include non-public nested types (that is, private, internal, and protected nested types) in the search.

This method returns only the nested types of the current type. It does not search the base classes of the current type. To find types that are nested in base classes, you must walk the inheritance hierarchy, calling GetNestedTypes at each level.

BindingFlags.Instance and BindingFlags.Static are ignored.

Calling this method with only the BindingFlags.Public flag or only the BindingFlags.NonPublic flag will return the specified nested types and does not require any other flags.

See System.Reflection.BindingFlags for more information.

If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the nested types of the class constraint.

If a nested type is generic, this method returns its generic type definition. This is true even if the enclosing generic type is a closed constructed type.

Note

If the current Type represents a generic type defined in C#, Visual Basic, or C++, its nested types are all generic even if they have no generic parameters of their own. This is not necessarily true of nested types defined in dynamic assemblies or compiled with the Ilasm.exe (IL Assembler).

For information on nested generic types, and on constructing nested generic types from their generic type definitions, see MakeGenericType.

See also

• BindingFlags
• DefaultBinder
• GetNestedType(String)