C# Custom Message Box that Returns Value OK or Cancel

Question

Because I want a nicer looking message box that actually appears where I want it to appear, I have to make my own custom message box.

How do I make one that returns a value?

The built in MessageBox.Show can return a DialogResult. I'm guessing I create something like that DialogResult class or can I use that class?

Answer 1

I appreciate James' answer, however I wanted to post an answer that provides the full result of what I did to solve this problem to create a more functional custom message box tool.

See the code below:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Drawing;

namespace MyProgram
{
    class CustomMessageBox
    {
        Label txtMsg = new Label();
        Button btnOK = new Button();
        Button btnCancel = new Button();
        Form newForm = new Form();

        private DialogResult spawnForm(string title, string text, MessageBoxButtons type)
        {            
            if(type == MessageBoxButtons.OKCancel)
            {
                newForm.Text = title;
                newForm.Controls.Add(txtMsg);
                txtMsg.AutoSize = true;
                txtMsg.Text = text;
                newForm.Width = txtMsg.Width + 125;
                newForm.Height = txtMsg.Height + 125;
                newForm.MaximumSize = new Size(newForm.Width, newForm.Height);
                newForm.MinimumSize = new Size(newForm.Width, newForm.Height);
                txtMsg.Location = new Point(newForm.Width / 2 - txtMsg.Width / 2, newForm.Height / 2 - 40);
                newForm.Controls.Add(btnOK);
                newForm.Controls.Add(btnCancel);
                btnOK.Text = "OK";
                btnCancel.Text = "Cancel";

                btnOK.Location = new Point(newForm.Width / 2 - btnOK.Width / 2 - 60, txtMsg.Location.Y + txtMsg.Height + 20);
                btnCancel.Location = new Point(newForm.Width / 2 - btnOK.Width / 2 + 40, btnOK.Location.Y);
                btnOK.DialogResult = DialogResult.OK;
                btnCancel.DialogResult = DialogResult.Cancel;
                newForm.StartPosition = FormStartPosition.CenterParent;
                return newForm.ShowDialog();
            } else
            {                
                newForm.Text = title;
                newForm.Controls.Add(txtMsg);
                txtMsg.AutoSize = true;
                txtMsg.Text = text;
                newForm.Width = txtMsg.Width + 125;
                newForm.Height = txtMsg.Height + 125;
                newForm.MaximumSize = new Size(newForm.Width, newForm.Height);
                newForm.MinimumSize = new Size(newForm.Width, newForm.Height);
                txtMsg.Location = new Point(newForm.Width / 2 - txtMsg.Width / 2 - 10, newForm.Height / 2 - 40);
                newForm.Controls.Add(btnOK);
                newForm.Controls.Remove(btnCancel);
                btnOK.Text = "OK";
                btnOK.Location = new Point(newForm.Width / 2 - btnOK.Width / 2 -10, txtMsg.Location.Y + txtMsg.Height + 20);
                btnOK.DialogResult = DialogResult.OK;
                newForm.StartPosition = FormStartPosition.CenterParent;
                return newForm.ShowDialog();
            }              
        }   

        public DialogResult Text(string title, string text, MessageBoxButtons type)
        {
            return spawnForm(title, text, type);
        }
    }
}

Answer 2

All you need to do is create your own custom form. All forms inherit for System.Windows.Forms.Form. When you want to show the form call ShowDialog() which returns a DialogResult when the form is closed. Depending on what you click on the message box you set the internal DialogResult property and call Close().

CustomMessageBox class

public partial class CustomMessageBox : Form
{
    public CustomMessageBox()
    {
        InitializeComponent();
    }

    private void btnOK_Click(object sender, EventArgs e)
    {
        // Some other logic for OK button
        this.DialogResult = DialogResult.OK;
        this.Close();
    }

    private void btnCancel_Click(object sender, EventArgs e)
    {
        // Some other logic for Cancel button
        this.DialogResult = DialogResult.Cancel;
        this.Close();
    }
}        

To use the message box it would just be

CustomMessageBox customMessage = new CustomMessageBox();
DialogResult result = customMessage.ShowDialog();

Of course you would have to add more to show an actual message and you could make a show method that is static like MessageBox.Show() but this is the basics for the DialogResult part.