For example: I define a class Person in a fiddle named PersonClass.
Then I base a new fiddle PersonUseExample on existing fiddle PersonClass, so I don't need to declare the class again, just démonstrate how I can use it.

The idea is probably easier to implementis but similar to the exiting request: https://dotnetfiddle.uservoice.com/forums/228764--net-fiddle-ideas/suggestions/6056568-allow-multiple-files-for-console-projects

Please enable vim key bindings. VsVim is one of the most downloaded Visual Studio extension, which is an indication of Vim key binding's popularity among .net devs.

Change the text color with Console.ForegroundColor

That the code can be used:
Console.ForegroundColor = ConsoleColor.DarkBlue;

Console.Write ("Hello");

Console.ForegroundColor = ConsoleColor.DarkRed;

Console.WriteLine ("World");

This would really help to make samples of bugs / issues in a repository. One could import all the files of a repository, then write a "Test" that fails and the owner of the repository could then check out why it fails easily.

See for example me manually uploading the files in a competitors product:
https://repl.it/@devedse/ErrorWhenLoadingJpgWithExif

I would like to be able to create projects that contain multiple files so that I can create tutorials to teach student.
The MVC project type for example allows for multiple files. but they are all together on screen and I can't close one down to focus on say the controller.

VS Code uses Theia https://www.theia-ide.org/index.html - Perhaps you could also use this in your UI?

Such as 'Def.1.1.1', which I successfully referenced but could not use.

The error is:

Compilation error (line 13, col 21): The name 'Def' does not exist in the current context.

The site shows that the package is "on disk", but '/usr/nugetCache/def' does not contain 1.1.1.

Is there a problem?

On .NET Core, you cannot do Console.ReadLine() as it doesn't work on that platform for some reason

https://dotnetfiddle.net/jsV9f5

Any plans to support an Azure Function like interface with files area for run.csx, function.json?

Lots of C# developers out there who can't afford to have an Azure Tenant that can help collaborate on our projects.

Now that Blazor server-side has been released and client-side in preview (due to be released with .Net 5 in November), you should think about supporting the project type on .Net Fiddle

In CodePen, you can show the HTML, CSS, and JS on one half of the iframe and the result on the other half, as well as open and close them by clicking on tabs located at the top of the iframe. It would be awesome if we could have the code be on one tab, and the console output on the other tab

Now every one plying pubg so they should forgot that so I'm help Full with you

lts support disappeared with net 5

With the growing online environment where people can piece things together via tools like zapier. It would be nice if we could
1. have a special end point url for a fiddle that would return only the values generated by the code.
2. (advanced request) allow these special endpoints to accept values via QueryString that could be used in the code.

Use case would be to run some function on some small piece of data and return it in the new format.This could vary based on each users business logic needs.

This creates confusing discrepancies, e.g. https://stackoverflow.com/questions/66063734/system-io-path-getfilenamewithoutextension-does-not-trim-a-file-path (caused by the fact that \ is not a file separator on Linux, but is on Windows).

I'm not unlearning the ctrl+s habbit just to use this site.

It would come in handy to be able to click either the .NET Fiddle title in the top left corner, or a New Fiddle button to start over. Now, you have to refresh the page or go back to http://dotnetfiddle.net to create a new fiddle.