ConsoleManager.cs

using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;
using System;

namespace IEEE754Inspector;

public static class ConsoleManager
{
	private const string Kernel32_DllName = "kernel32.dll";

	[DllImport(Kernel32_DllName)]
	private static extern bool AllocConsole();

	[DllImport(Kernel32_DllName)]
	private static extern bool FreeConsole();

	[DllImport(Kernel32_DllName)]
	private static extern nint GetConsoleWindow();

	[DllImport(Kernel32_DllName)]
	private static extern int GetConsoleOutputCP();

	public static bool HasConsole {
		get { return GetConsoleWindow() != nint.Zero; }
	}

	/// <summary>
	/// Creates a new console instance if the process is not attached to a console already.
	/// </summary>
	public static void Show()
	{
		//#if DEBUG
		if (!HasConsole) {
			AllocConsole();
			InvalidateOutAndError();
		}
		//#endif
	}

	/// <summary>
	/// If the process has a console attached to it, it will be detached and no longer visible. Writing to the System.Console is still possible, but no output will be shown.
	/// </summary>
	public static void Hide()
	{
		//#if DEBUG
		if (HasConsole) {
			SetOutAndErrorNull();
			FreeConsole();
		}
		//#endif
	}

	public static void Toggle()
	{
		if (HasConsole) {
			Hide();
		}
		else {
			Show();
		}
	}

	static void InvalidateOutAndError()
	{
		Type type = typeof(Console);

		System.Reflection.FieldInfo _out = type.GetField("_out",
			System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic);

		System.Reflection.FieldInfo _error = type.GetField("_error",
			System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic);

		System.Reflection.MethodInfo _InitializeStdOutError = type.GetMethod("InitializeStdOutError",
			System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.NonPublic);

		Debug.Assert(_out != null);
		Debug.Assert(_error != null);

		Debug.Assert(_InitializeStdOutError != null);

		_out.SetValue(null, null);
		_error.SetValue(null, null);

		_InitializeStdOutError.Invoke(null, new object[] { true });
	}

	static void SetOutAndErrorNull()
	{
		Console.SetOut(TextWriter.Null);
		Console.SetError(TextWriter.Null);
	}
}