ReadLine.Reboot

ReadLine.Reboot is a reboot of Toni Solarin-Sodara's original ReadLine that is discontinued. It's 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, as long as they run on .NET Framework 4.8 or at least .NET Core 3.1.

Shortcut Guide

Note: Some keys conflict with terminal emulator keybindings.

Keybinding	Action
Ctrl+A / HOME	Beginning of line
Ctrl+E / END	End of line
Ctrl+B / ←	Backward one character
Ctrl+F / →	Forward one character
Alt+B	Backward one word
Alt+F	Forward one word
Ctrl+C	Send EOF
Ctrl+H / Backspace	Delete previous character
Ctrl+D / Delete	Delete succeeding character / End of line if nothing
Ctrl+L	Clear screen and rewrite current line
Ctrl+U	Cut text to the start of line
Ctrl+K	Cut text to the end of line
Ctrl+W / Alt+Backspace	Cut previous word
Alt+D	Cut next word
Alt+\	Cut horizontal line
Ctrl+Y	Yank (paste the cut content)
Ctrl+T	Switch two characters
Alt+T	Switch two words
Alt+L	Make word lowercase
Alt+U	Make word uppercase
Alt+C	Make char uppercase and move to the end of word
Alt+V	Make char lowercase and move to the end of word
Shift+Alt+#	Add comment # to the beginning of the line
Alt+Tab	Insert the TAB character verbatim *
Shift+Alt+&	Perform tilde expansion
Ctrl+J / Enter	End of line
Ctrl+Shift+_	Undo the last change **
Alt+R	Undos all the changes
Ctrl+N / ↓	Forward in history
Ctrl+P / ↑	Backward in history
Shift+Alt+<	First history
Shift+Alt+>	Last history (Go back to current line)
Alt+.	Add last argument to current input
Ctrl+I / Tab	Command line completion
Shift+Ctrl+I / Shift+Tab	Backwards command line completion
Alt+Shift+?	List possible completion
Shift+Alt+*	Dump all suggestions to current line
Alt+0-9	Argument number add
Alt+-	Argument number negation

• *: Conflicts with Alt+Tab on Windows.
• **: Conflicts with Ctrl+Shift+_ on Windows Command Prompt

Installation

Available on NuGet

Visual Studio:

PM> Install-Package ReadLine.Reboot

.NET Core CLI:

dotnet add package ReadLine.Reboot

Comparison as of ReadLine.Reboot 3.0.0

Here, we'll compare some of the base features between Original ReadLine, Latency's ReadLine, and ReadLine.Reboot.

Feature	Original	Latency's	ReadLine.Reboot	Notes
CTRL + A / HOME	Works	Works	Works
CTRL + E / END	Works	Works	Works
CTRL + B / LEFT	Works	Malfunction	Works	Cursor goes backwards too much until the crash occurs
CTRL + F / RIGHT	Works	Works	Works
CTRL + C	Nonfunctional	Malfunction	Works	Unimplemented in original, Latency's implementation just always exits the app, Ours works if you have CtrlCEnabled set to true
CTRL + H / BACKSPACE	Works	Malfunction	Works	Cursor goes backwards too much until the crash occurs
CTRL + D / DEL	Works	Works	Works
CTRL + L / ESC	Works	Malfunction	Works	Cursor goes backwards too much until the crash occurs
CTRL + U	Works	Malfunction	Works	Cursor goes backwards too much until the crash occurs
CTRL + K	Works	Malfunction	Works	Cursor goes backwards too much until the crash occurs
CTRL + W	Partial	Partial	Works	Wipe all whitespace before erasure in original and Latency's
ALT + BACKSPACE	Nonfunctional	Malfunction	Works	Unimplemented in original and Latency, cursor goes backwards too much until the crash occurs (Latency)
CTRL + T	Works	Malfunction	Works	Corrupts output
CTRL + J	Partial	Partial	Works	Appends ACTUAL newline on Windows in original and Latency's
CTRL + N / DOWN (history)	Partial	Malfunction	Works	Clears line in original, corrupts output in Latency's
CTRL + P / UP (history)	Partial	Malfunction	Works	Clears line in original, corrupts output in Latency's
TAB (autocomplete)	Works	Works	Works
TAB (no autocomplete)	Partial	Partial	Works	Whole ReadLine doesn't really support tab chars, ReadLine.Reboot treats tabs as eight spaces
SHIFT + TAB (autocomplete)	Works	Works	Works
SHIFT + TAB (no autocomplete)	Partial	Partial	Works	Whole ReadLine doesn't really support tab chars, ReadLine.Reboot treats tabs as eight spaces

Usage

This section shows you how to use this library to read the lines and manage history. Just add this to the top of the source file you want to use ReadLine.Reboot on:

using ReadLineReboot;

Input

Note: The (prompt>) is optional

Read input

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

Read input with default

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

Read input with custom prompt handler

ReadLine.WritePrompt = (prompt) => Console.Write($">> {prompt}");
string input = ReadLine.Read("(prompt)> ", "default");

Read password

string password = ReadLine.ReadPassword("(prompt)> ");

Read password with password mask

string password = ReadLine.ReadPassword("(prompt)> ", '*');

Interrupt reading

ReadLine.Interruptible = true;
ReadLine.InterruptRead();

Custom shortcuts

Add custom shortcut

ReadLine.AddCustomBinding(new ConsoleKeyInfo('R', ConsoleKey.R, true, true, true), FunctionName);

Change custom shortcut

ReadLine.ChangeCustomBinding(new ConsoleKeyInfo('R', ConsoleKey.R, true, true, true), AlternateFunctionName);

Remove custom shortcut

ReadLine.RemoveCustomBinding(new ConsoleKeyInfo('R', ConsoleKey.R, true, true, true));

History management

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

// Get command history
ReadLine.GetHistory();

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

// Clear history
ReadLine.ClearHistory();

// Set history
List<string> newHistory = new() { "apt update", "apt dist-upgrade" };
ReadLine.SetHistory(newHistory);

// Disable history (default)
ReadLine.HistoryEnabled = false;

// Enable history
ReadLine.HistoryEnabled = true;

Auto-Completion

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

class AutoCompletionHandler : IAutoCompleteHandler
{
    // characters to start completion from
    public char[] Separators { get; set; } = new char[] { ' ', '.', '/' };

    // text - The current text entered in the console
    // index - The index of the terminal cursor within {text}
    public string[] GetSuggestions(string text, int index)
    {
        if (text.StartsWith("git "))
            return new string[] { "init", "clone", "pull", "push" };
        else
            return null;
    }
}

ReadLine.AutoCompletionHandler = new AutoCompletionHandler();

You can disable and enable the auto-completion feature below.

// Disable history (default)
ReadLine.AutoCompletionEnabled = false;

// Enable history
ReadLine.AutoCompletionEnabled = true;

Credits

Author	For
Toni Solarin-Sodara	Original ReadLine
Aptivi	Rebooting the ReadLine project

License

MIT License

Copyright (c) 2017 Toni Solarin-Sodara
Copyright (c) 2022 Aptivi

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.