protected override void OnHandleDestroyed(EventArgs e)
{
base.OnHandleDestroyed(e);
if (_currentForm == this)
{
_currentForm = null;
}
}
protected override void OnHandleCreated(EventArgs e)
{
base.OnHandleCreated(e);
if (_currentForm != null && _currentForm.IsHandleCreated)
{
_currentForm.Close();
}
_currentForm = this;
}