窗口关闭事件

  private void jihua_FormClosing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            if (DialogResult.Cancel == MessageBox.Show("确定关闭吗？？？", "系统提示！！！", MessageBoxButtons.OKCancel, MessageBoxIcon.Question))
            {
                e.Cancel = true;
            }
        }