/readline

A Pure C# GNU-Readline like library for .NET/.NET Core

Primary LanguageC#MIT LicenseMIT

Windows build status License: MIT NuGet version

ReadLine

ReadLine is a GNU Readline like library built in pure C#. It can serve as a drop in replacement for the inbuilt Console.ReadLine() and brings along with it some of the terminal goodness you get from unix shells, like command history navigation and tab auto completion.

It is cross platform and runs anywhere .NET is supported, targeting netstandard1.3 means that it can be used with .NET Core as well as the full .NET Framework.

Shortcut Guide

Shortcut Comment
Ctrl+A / HOME Beginning of line
Ctrl+B / Backward one character
Ctrl+C Send EOF
Ctrl+E / END End of line
Ctrl+F / Forward one character
Ctrl+H / Backspace Delete previous character
Tab Command line completion
Shift+Tab Backwards command line completion
Ctrl+J / Enter Line feed
Ctrl+K Cut text to the end of line
Ctrl+L Clear line
Ctrl+M Same as Enter key
Ctrl+N / Forward in history
Ctrl+P / Backward in history
Ctrl+U Cut text to the start of line
Ctrl+W Cut previous word
Backspace Delete previous character

Usage

Add ReadLine as a dependency

.NET Core CLI

dotnet add package ReadLine

Package Manager Console

Install-Package ReadLine

Read input from the console

string input = ReadLine.Read("(prompt)> ");

Note: The (prompt>) is optional

History management

// Get command history
ReadLine.GetHistory();

// Add command to history
ReadLine.AddHistory("dotnet run");

// Clear history
ReadLine.ClearHistory();

Note: History information is persisted for an entire application session. Also, calls to ReadLine.Read() automatically adds the console input to history

Auto-Completion

// t:string - The current text entered in the console
// s:int - The index of the command fragment that needs to be completed
// returns string[]
ReadLine.AutoCompletionHandler = (t, s) =>
{
    string[] suggestions = /* logic to generate suggestions */;
    // return string array of suggestions 
    // or null if no suggestions are available
    return suggestions;
};

Note: If no "AutoCompletionHandler" is set, tab autocompletion will be disabled

Contributing

Contributions are highly welcome. If you have found a bug or if you have a feature request, please report them at this repository issues section.

Things you can help with:

  • Achieve better command parity with GNU Readline.
  • Add more test cases.

License

This project is licensed under the MIT license. See the LICENSE file for more info.