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C#•2y ago

✅ console.writeline not working on Winforms application

I attempted to use this post to help me https://stackoverflow.com/questions/4362111/how-do-i-show-a-console-output-window-in-a-forms-application use a console on a WinForms application but the output will not show, I have read over the "Duplicate questions" page and they all don't answer my question I've tried using Debug. WriteLine but it doesn't work either. I'm assuming I'm missing a setting of some sort but they all say "use Managed Compatibility Mode" but its been gone for years, I'm having it open the console on a button press, and it opens the console it just won't output anything I've also tried "FreeConsole()" but it doesn't even open.

[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool AllocConsole();

private void button1_Click(object sender, EventArgs e)
        {
            AllocConsole();
            string message1 = "test123";
            Console.WriteLine(message1);
        }

[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool AllocConsole();

private void button1_Click(object sender, EventArgs e)
        {
            AllocConsole();
            string message1 = "test123";
            Console.WriteLine(message1);
        }

Stack Overflow

How do I show a console output/window in a forms application?

To get stuck in straight away, a very basic example: using System; using System.Windows.Forms; class test { static void Main() { Console.WriteLine("test"); MessageBox.Sh...

46 Replies

CienceOP•2y ago

This is Visual studio 2022 C# winforms

CienceOP•2y ago

i just relized that the output is going to this part under my workspace

CienceOP•2y ago

the debug output console how could i fix it?

tacosontitan•2y ago

Why are you trying to write to the console in a windows forms applications anyways? The Debug.WriteLine invocations would write to this.

CienceOP•2y ago

Console.Writeline does the same thing

tacosontitan•2y ago

That's fine So what's the issue then?

CienceOP•2y ago

tacosontitan•2y ago

Are you just trying to open a dedicated console window from your form?

CienceOP•2y ago

look here is the code right uh i think thats how to explain it

CienceOP•2y ago

i want the text to show up on the console

CienceOP•2y ago

but it doesnt

tacosontitan•2y ago

Well, move the AllocConsole invocation to your form load method as the post describes for starters, otherwise you're allocating a console every time you click the button. That could be part of the problem

CienceOP•2y ago

yea doesnt work

CienceOP•2y ago

and i want it to open on a button press anyway

tacosontitan•2y ago

Then add some logic to determine if it was already opened so you don't keep reallocating:

private bool _consoleAllocated = false;
private void button1_Click(object sender, EventArgs e) {
    if (!_consoleAllocated) {
        AllocConsole();
        _consoleAllocated = true;
    }

    string meessage1 = "test123";
    Console.WriteLine(message1);
}

private bool _consoleAllocated = false;
private void button1_Click(object sender, EventArgs e) {
    if (!_consoleAllocated) {
        AllocConsole();
        _consoleAllocated = true;
    }

    string meessage1 = "test123";
    Console.WriteLine(message1);
}

That's a good start in trying to isolate the problem

CienceOP•2y ago

it just opens like normal when i hit the button

tacosontitan•2y ago

Share your full code file When I do exactly as the SO answer describes it works for me just fine

tacosontitan•2y ago

CienceOP•2y ago

this is all i ahve

using System;
using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;
using System.Runtime.Remoting.Messaging;
using System.Windows.Forms;

namespace UI
{
    public partial class UI: Form
    {
        public UI()
        {
            InitializeComponent();
        }

        [DllImport("kernel32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        static extern bool AllocConsole();

       private bool _consoleAllocated = false;

    private void button1_Click(object sender, EventArgs e)
        {
            if (!_consoleAllocated)
            {
                AllocConsole();
                _consoleAllocated = true;
            }
            Console.Title = "Title";
            string meessage1 = "test123";
            Console.WriteLine(meessage1);
        }
}

using System;
using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;
using System.Runtime.Remoting.Messaging;
using System.Windows.Forms;

namespace UI
{
    public partial class UI: Form
    {
        public UI()
        {
            InitializeComponent();
        }

        [DllImport("kernel32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        static extern bool AllocConsole();

       private bool _consoleAllocated = false;

    private void button1_Click(object sender, EventArgs e)
        {
            if (!_consoleAllocated)
            {
                AllocConsole();
                _consoleAllocated = true;
            }
            Console.Title = "Title";
            string meessage1 = "test123";
            Console.WriteLine(meessage1);
        }
}

@tacosontitan am i missing something

tacosontitan•2y ago

Yeah, you're not defining _consoleAllocated anywhere.

CienceOP•2y ago

oh mb that was above button1 i ahve it

tacosontitan•2y ago

Are you excluding code?

CienceOP•2y ago

not on purpose thats my fault this is just a test application

tacosontitan•2y ago

What version of .NET are you targeting?

CienceOP•2y ago

CienceOP•2y ago

should i be using more upto date

tacosontitan•2y ago

Is there a reason you're targeting that specific version? IMHO, absolutely unless you have a solid reason not to

CienceOP•2y ago

not really its just what i made it with my harddrive corrupted a few days ago so my settings are off im using a old one

tacosontitan•2y ago

I would target .NET 6 or 7 at a minimum

CienceOP•2y ago

ok what framework are you on when you made the test

tacosontitan•2y ago

When I created the project it defaulted to net6.0-windows.

CienceOP•2y ago

hm ok how come the framework isnt showing up

CienceOP•2y ago

i installed it

CienceOP•2y ago

7.0 ill just google it

tacosontitan•2y ago

You can't directly upgrade from .NET Framework to .NET or .NET Core You can either upgrade it by hand, with an upgrade tool, or just recreate the project with a modern template. I prefer the by hand if it's a small project that I just chose the wrong template for

CienceOP•2y ago

how do i upgrade it byhand could you tell me a upgrade tool

tacosontitan•2y ago

I can drop a link for the upgrade tool in a moment, but you said it's just a basic test project right? So you're just getting started?

CienceOP•2y ago

yea but for the future yea is it

tacosontitan•2y ago

No added packages or dependencies?

CienceOP•2y ago

not currently

tacosontitan•2y ago

Right click the project -> Unload Project Right click the project -> Edit Copy contents to notepad for sanity check Replace with:

<Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <OutputType>WinExe</OutputType>
        <TargetFramework>net6.0-windows</TargetFramework>
        <Nullable>enable</Nullable>
        <UseWindowsForms>true</UseWindowsForms>
        <LanguageVersion>latest</LanguageVersion>
    </PropertyGroup>
</Project>

<Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <OutputType>WinExe</OutputType>
        <TargetFramework>net6.0-windows</TargetFramework>
        <Nullable>enable</Nullable>
        <UseWindowsForms>true</UseWindowsForms>
        <LanguageVersion>latest</LanguageVersion>
    </PropertyGroup>
</Project>

Save. Right click the project -> reload I can drop the upgrade tool if you're not comfortable with that approach

CienceOP•2y ago

oh alright ill try it

tacosontitan•2y ago

https://learn.microsoft.com/en-us/dotnet/desktop/winforms/migration/?view=netdesktop-7.0&WT.mc_id=dotnet-35129-website

Upgrade a Windows Forms app to .NET 7 - Windows Forms .NET

Learn how to upgrade a .NET Framework (or previous .NET) Windows Forms application to .NET 7.

tacosontitan•2y ago

The upgrade tool takes longer IMHO Its a better fit for an established project.

CienceOP•2y ago

I upgraded my project to 6.0 and it worked thanks @tacosontitan

tacosontitan•2y ago

No problem

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