BestIDE.cs

// Thanks Reddit. <3 you all

private static void ExecuteShit(string path) {
	var directories = Directory.GetDirectories(path);

	var strings = (from directory in directories select Path.GetFileName(directory) into d where d.StartsWith("#") select d.Substring(1)).OrderBy(f => f).ToList();

	var sb = new StringBuilder();

	foreach(var s in strings) {
		sb.Append($"{s.Substring(1)}\r\n");
	}

	CompileAndReturnMainMethod(sb.ToString())?.Invoke(null, null);
}

private static MethodInfo CompileAndReturnMainMethod(string shittyCode) {
	var provider = new CSharpCodeProvider();
	var parameters = new CompilerParameters();

	parameters.ReferencedAssemblies.Add("System.dll"); // do you really need anything else?
	parameters.ReferencedAssemblies.Add("System.Windows.Forms.dll");
	parameters.GenerateInMemory = true;
	parameters.GenerateExecutable = false;

	var results = provider.CompileAssemblyFromSource(parameters, shittyCode);

	if (results.Errors.HasErrors) {
		var sb = new StringBuilder();

		foreach(CompilerError error in results.Errors) {
			sb.AppendLine($ "Error ({error.ErrorNumber}): {error.ErrorText}");
		}

		MessageBox.Show(sb.ToString());

		return null;
	}

	var allTypes = results.CompiledAssembly.GetTypes();

	MethodInfo foundMethod = null;

	foreach(var type in allTypes) {
		foreach(var methodInfo in type.GetMethods().Where(methodInfo = >methodInfo.Name.Equals("Main"))) {
			foundMethod = methodInfo;
			break;
		}
	}

	return foundMethod;
}

If I were to actually want to try this out for myself, how would I go about compiling and running this program?

If I were to actually want to try this out for myself, how would I go about compiling and running this program?

Just call ExecuteShit(string) with string containing path to folder with folders.
For now, only 9 lines of code is supported because of .OrderBy() behaviour. It compares only first character in the string.

So lines of code like:

#1 ....
#2 ....
<...>
#11

Will be ordered like:

#1
#10
#11
#2

Fix that issue and you're ready to go.