Dotnet Unused Code Analyzer - VS Code Extension

Detect and highlight unused code in .NET solutions directly in Visual Studio Code using Roslyn static analysis.

Features

• On-Demand Analysis: Analyze your entire workspace or just the current file
• Inline Diagnostics: See unused code warnings directly in your editor with squiggly underlines
• Problems Panel: All unused symbols listed in VS Code's Problems panel
• Tree View: Sidebar panel showing unused symbols organized by type (Methods, Properties, Fields)
• Configurable Severity: Set diagnostic severity (Error, Warning, Information, Hint)
• Jump to Definition: Click any unused symbol in the tree view to navigate to its location
• Export Reports: Generate JSON reports of unused code (coming soon)

Requirements

This extension requires the dotnet-unused CLI tool to be installed:

dotnet tool install --global DotnetUnused

See the CLI installation guide for more options.

Usage

Commands

Access commands via Command Palette (Ctrl+Shift+P / Cmd+Shift+P):

• Dotnet Unused: Analyze Workspace for Unused Code - Analyze entire solution/project
• Dotnet Unused: Analyze Current File for Unused Code - Analyze only the current C# file's project
• Dotnet Unused: Clear Unused Code Diagnostics - Clear all diagnostics from the editor
• Dotnet Unused: Export Unused Code Report (JSON) - Export analysis results (coming soon)

Tree View

The "Dotnet Unused" sidebar panel shows:

• Unused symbols grouped by type (Methods, Properties, Fields)
• File location and line number for each symbol
• Click any item to jump to its definition

Context Menu

Right-click on .sln or .csproj files in the Explorer to analyze them directly.

Extension Settings

Configure the extension in VS Code settings:

• dotnet-unused.cliPath: Path to dotnet-unused CLI tool (leave empty for global installation)
• dotnet-unused.excludePublic: Exclude public members from detection (default: true)
• dotnet-unused.diagnosticSeverity: Severity level for diagnostics (Error, Warning, Information, Hint)
• dotnet-unused.useTerminal: Show output in integrated terminal instead of output window (default: true)
• dotnet-unused.autoRunOnSave: Automatically analyze when C# files are saved (default: false)

How It Works

The extension integrates with the dotnet-unused CLI tool:

1. Runs analysis on your .NET solution or project
2. Parses the JSON output from the CLI
3. Creates VS Code diagnostics for unused symbols
4. Updates the tree view with results
5. Allows navigation to unused code locations

Supported Project Types

• .NET Core 2.0+
• .NET 5+
• .NET 6/7/8/9+
• .NET Framework 4.x (requires Visual Studio MSBuild)
• SDK-style projects
• Legacy .csproj format

Known Limitations

• Static analysis only - does not detect runtime or reflection-based usage
• Conservative approach may miss some unused code to avoid false positives
• No incremental analysis - full solution analysis on each run

Troubleshooting

"dotnet-unused CLI tool not found"

Install the CLI tool globally:

dotnet tool install --global DotnetUnused

Or specify a custom path in settings:

{
  "dotnet-unused.cliPath": "/path/to/dotnet-unused"
}

Analysis is slow

• Use "Analyze Current File" for faster feedback
• Disable autoRunOnSave for large solutions
• Consider analyzing only specific projects instead of entire solutions

Contributing

Issues and contributions welcome at GitHub.

License

MIT - See LICENSE file for details.