source: Common/FormEx.cs

using System;
using System.Drawing;
using System.Windows.Forms;

namespace Common
{
    public class FormEx : Form
    {
        public FormEx() : base()
        {
            FormClosed += new FormClosedEventHandler(FormEx_FormClosed);
        }

        protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);
            Theme.UseTheme(this);
            DpiScaling.Apply(this);
            Icon = Icon.ExtractAssociatedIcon(Application.ExecutablePath);
            new FormDimensions().Load(this, Owner);
        }

        private void FormEx_FormClosed(object sender, FormClosedEventArgs e)
        {
            new FormDimensions().Save(this);
        }

        protected override bool ProcessDialogKey(Keys keyData)
        {
            if (ModifierKeys == Keys.None && keyData == Keys.Escape)
            {
                Close();
                return true;
            }
            return base.ProcessDialogKey(keyData);
        }
    }
}