Winform程序退出前的确认

 private void FrmMain_FormClosing(object sender, FormClosingEventArgs e)
        {
            DialogResult result = MessageBox.Show("确认退出吗？","退出询问"
                ,MessageBoxButtons.OKCancel,MessageBoxIcon.Question);
            if(result != DialogResult.OK)
            {
                e.Cancel = true;//告诉窗体关闭这个任务取消
            }
        }