C# Implementations CodeLens

See how many classes implement your C# interfaces — and jump straight to them.

This extension shows a Rider-style N implementations CodeLens above interfaces, interface members, and abstract/virtual members in C# files.

It complements the N references CodeLens you already get from the official C# extension — references tell you who calls a symbol, this tells you who implements it. If you're coming to VS Code from JetBrains Rider or Visual Studio and miss the implementations counter, this brings it back.

Features

• Implementation counts as CodeLens above:
  • interface declarations and every member inside them (methods, properties, events, indexers)
  • abstract and virtual members of classes
  • abstract class declarations
• Click to navigate: one implementation jumps directly to it; two or more open the peek view so you can browse all implementations inline
• No noise: override members and ordinary concrete members get no lens
• Fast in large files: counts are resolved lazily, only for the lenses scrolled into view
• No reloads: all settings apply immediately

Requirements

• VS Code 1.101 or newer.
• The official C# extension (or C# Dev Kit) must be installed and running — this extension does no C# parsing of its own; it queries the C# language server through VS Code's document-symbol and implementation providers.

Settings

Setting	Default	Description
csharpImplementationsCodeLens.enabled	true	Show the implementations CodeLens in C# files.
csharpImplementationsCodeLens.showOnInterfaceMembers	true	Show the lens on members declared inside interfaces.
csharpImplementationsCodeLens.showOnAbstractVirtualMembers	true	Show the lens on abstract/virtual class members.
csharpImplementationsCodeLens.hideWhenZero	false	Hide the lens entirely when there are no implementations, instead of showing "no implementations".

Development

npm install
npm run build     # type-check + bundle to dist/extension.js
npm run watch     # incremental rebuild (used by F5)
npm run package   # produce the .vsix

Press F5 to launch an Extension Development Host with the watch build, then open sample/Sample.cs to see the lenses (give the C# language server a moment to load).

How it works

Lenses are emitted unresolved from the document symbol tree and only resolved (one implementation lookup each) when they scroll into view, so large files stay fast. Implementation lookups are answered by the C# language server (Roslyn) via VS Code's executeImplementationProvider — the same engine behind Go to Implementations (Ctrl+F12 / ⌘F12).