WebAssembly(Wasm) CSharp Editor

日本語版のreadmeもあります。/ Japanese version of this document is available.

The majority of this project is C# code, although the display on Github may show it as a javascript project.

Summary

A C# development environment that allows you to edit and execute code in a browser.

Details

By using WebAssembly, the C# compiler and user code are executed in the browser. The goal is to provide a development experience equivalent to that of existing development environments published as desktop applications, without the need for installation or other work. I also plan to create a learning course for beginners who are beginning to learn C# by implementing a judging system similar to that used in competitive programming.

How to use

Requirements

• Latest web browser; IE is not supported; the latest version of Google Chrome is recommended.
• Service Worker enabled environment. firefox's private browsing mode will not work with Service Worker.

Usage

You can try the latest development build at the Github Pages Almost all C# features are supported. The language version is C#10. You can use standard input/output APIs such as Console.WriteLine and Console.ReadLine as you normally do when writing console applications.

Progress

Implemented

• A code editor with syntax highlighting, using the CodeMirror library.
• Compilation and execution of user-written code.
• Compile and execute in a separate thread using the Web workers API.
• To display the standard output in a virtual console implemented in HTML.
• Implementation of Console.ReadLine based on synchronous waiting between Workers using Service Worker and XHR.

Implementing

High priority

• Interruption of code execution and compilation.
• Judge system implementation.

Middle priority

• Saving and exporting code.
• Accepting the defaulted code of the code editor as the URL query string.
• Code formatter implementation.
• Better syntax highlighting. (Syntax highlighting based on parsing)
• Auto-completion of code (like intellisense)

Low priority

• Changing compile option.
• Creating learning cource.
• Store the code online.

Known bugs

• 404 error workaround for SPA is not working.
• The cache created by the Blazor runtime and the offline cache created by the service worker are duplicated.
• The implementation of Console.Read is different from the specification. The specification is misinterpreted.
• If the code written by the user allocates too much memory or writes too much to the console, the application will crash due to out of memory.
• When user-written code causes stack overflow due to infinite recursive function calls, etc., the runtime crashes instead of raising a .NET exception.
• The DLL to be loaded does not reflect the culture of the application.