public class BaseForm : Form
{
public BaseForm()
{
    if (LicenseManager.UsageMode == LicenseUsageMode.Designtime) return;
    this.Load += BaseForm_Load;
    this.FormClosed += BaseForm_FormClosed;
}
private IEnumerable<Control> GetAllControls(Control control)
{
    var controls = control.Controls.Cast<Control>();
    return controls.SelectMany(ctrl => GetAllControls(ctrl)).Concat(controls);
}
void BaseForm_FormClosed(object sender, FormClosedEventArgs e)
{
    Log(string.Format("{0} Closed", this.Name));
}
void BaseForm_Load(object sender, EventArgs e)
{
    Log(string.Format("{0} Opened", this.Name));
    GetAllControls(this).OfType<Button>().ToList()
        .ForEach(x => x.Click += ButtonClick);
}
void ButtonClick(object sender, EventArgs e)
{
    var button = sender as Button;
    if (button != null) Log(string.Format("{0} Clicked", button.Name));
}
public void Log(string text)
{
    var file = System.IO.Path.Combine(Application.StartupPath, "log.txt");
    text = string.Format("{0} - {1}", DateTime.Now, text);
    System.IO.File.AppendAllLines(file, new string[] { text });
}