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Tag: extension-members

4 posts

2026-08-18 errors csharp csharp-14

Fix: The call is ambiguous between the following methods or properties after moving to C# 14 extension members

CS0121 after moving an extension method into a C# 14 extension block: the compiler still emits the old static form. Delete the duplicate or qualify the call.

2026-07-18 dotnet-11 csharp csharp-15

C# 15 Extension Indexers Round Out Extension Members in .NET 11 Preview 6

Extension indexers landed in .NET 11 Preview 6, letting you add this[...] access to types you do not own. They complete the extension members story that started with methods and properties in C# 14.

2026-06-24 how-to csharp csharp-14

How to declare extension properties in C# 14

Extension properties land in C# 14 through the new extension block. Declare get-only, settable, static, and generic extension properties, why auto-properties are rejected, and how the compiler lowers them to get_/set_ accessors.

2026-02-08 csharp csharp-14 dotnet-10

C# 14 Extension Members: Extension Properties, Operators, and Static Extensions

C# 14 introduces extension members, allowing you to add extension properties, operators, and static members to existing types using the new extension keyword.