C# winform窗体关闭按钮

添加form的FormClosing事件 

         /// <summary>

         /// 主窗口自带的关闭按钮

         /// </summary>

         /// <param name="sender"></param>

         /// <param name="e"></param>

          private void MainForm_FormClosing(object sender, FormClosingEventArgs e)

         {

             DialogResult result;

             result = MessageBox.Show("确定退出吗？", "退出", MessageBoxButtons.OKCancel, MessageBoxIcon.Question);

             if (result == DialogResult.OK)

             {

                 Application.ExitThread();

             }

             else

                 e.Cancel = true;

         }