[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[[["\u003cp\u003eThis document covers the \u003ccode\u003eExtension\u003c/code\u003e class within the \u003ccode\u003eGoogle.Protobuf\u003c/code\u003e namespace, which is part of the Google.Protobuf.dll assembly.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eExtension\u003c/code\u003e class is an abstract class that represents a non-generic extension definition and is currently considered experimental.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eExtension\u003c/code\u003e class inherits from \u003ccode\u003eobject\u003c/code\u003e and provides access to inherited members, as well as having two derived types: \u003ccode\u003eExtension<TTarget, TValue>\u003c/code\u003e and \u003ccode\u003eRepeatedExtension<TTarget, TValue>\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eExtension\u003c/code\u003e class includes a constructor \u003ccode\u003eExtension(int fieldNumber)\u003c/code\u003e for internal use, and it exposes a \u003ccode\u003eFieldNumber\u003c/code\u003e property that returns an integer representing the field number of the extension.\u003c/p\u003e\n"],["\u003cp\u003eThe latest version discussed in the documentation is 3.27.1, with two other versions, 3.23.0 and 3.15.8 also listed for reference.\u003c/p\u003e\n"]]],[],null,["# Class Extension (3.27.1)\n\nVersion latestkeyboard_arrow_down\n\n- [3.27.1 (latest)](/dotnet/docs/reference/Google.Protobuf/latest/Google.Protobuf.Extension)\n- [3.23.0](/dotnet/docs/reference/Google.Protobuf/3.23.0/Google.Protobuf.Extension)\n- [3.15.8](/dotnet/docs/reference/Google.Protobuf/3.15.8/Google.Protobuf.Extension) \n\n public abstract class Extension\n\nRepresents a non-generic extension definition. This API is experimental and subject to change. \n\nInheritance\n-----------\n\n[object](https://learn.microsoft.com/dotnet/api/system.object) \\\u003e Extension \n\nInherited Members\n-----------------\n\n[object.Equals(object)](https://learn.microsoft.com/dotnet/api/system.object.equals#system-object-equals(system-object)) \n[object.Equals(object, object)](https://learn.microsoft.com/dotnet/api/system.object.equals#system-object-equals(system-object-system-object)) \n[object.GetHashCode()](https://learn.microsoft.com/dotnet/api/system.object.gethashcode) \n[object.GetType()](https://learn.microsoft.com/dotnet/api/system.object.gettype) \n[object.MemberwiseClone()](https://learn.microsoft.com/dotnet/api/system.object.memberwiseclone) \n[object.ReferenceEquals(object, object)](https://learn.microsoft.com/dotnet/api/system.object.referenceequals) \n[object.ToString()](https://learn.microsoft.com/dotnet/api/system.object.tostring) \n\nDerived Types\n-------------\n\n[Extension\\\u003cTTarget, TValue\\\u003e](/dotnet/docs/reference/Google.Protobuf/latest/Google.Protobuf.Extension-2) \n[RepeatedExtension\\\u003cTTarget, TValue\\\u003e](/dotnet/docs/reference/Google.Protobuf/latest/Google.Protobuf.RepeatedExtension-2)\n\nNamespace\n---------\n\n[Google.Protobuf](/dotnet/docs/reference/Google.Protobuf/latest/Google.Protobuf)\n\nAssembly\n--------\n\nGoogle.Protobuf.dll\n\nConstructors\n------------\n\n### Extension(int)\n\n protected Extension(int fieldNumber)\n\nInternal use. Creates a new extension with the specified field number.\n\nProperties\n----------\n\n### FieldNumber\n\n public int FieldNumber { get; }\n\nGets the field number of this extension"]]
