using System; namespace Tester { // ordinary outer class public partial class PartialOuterPartialInner { public PartialOuterPartialInner () { } public partial class PartialMiddle { // First part of inner public partial class PartialInner { // member a public int a = 0; } // middlea member public int middlea = 0; } // a outer member public int outera = 0; public partial class PartialMiddle { // middle b member public int middleb = 0; // Second part of inner public partial class PartialInner { // member b public int b = 0; } } } }