c#之異常處理tcbs_try_catch_finally

 private void ReadPwdThread()
        {
            //開啟串列埠
            if (!OpenComm()) --呼叫另一方法
            {
                  //呼叫另一異常處理方法
                CoreMessageBox.Show("開啟密碼鍵盤失敗");
                return;//返回
            }
            bool flag = true;//給flag提供值true
  
             //try塊開始實際工作了哈
            try
            {

                //開啟密碼鍵盤並有語音提示  
                //呼叫另一開啟密碼鍵盤方法，方法引數在類中定義為常量string const        
                OpenPinPad(Voice);

                //讀取密碼
                //同上
                passwordOnce(ReveivePassword());

                //再次讀取密碼
                OpenPinPad(VoiceAgain);

                //讀取密碼
                passwordTwice(ReveivePassword());
            }
                 //抓異常進行處理，基類exception
            catch (Exception)
            {
              //空體沒有處理
            }
              //try-catch如新增finally，一般用於關閉一些佔用的資源或必須要作的工作
              //try-catch-finally各程式碼塊可進行n級內嵌
            finally
            {
                try
                {
                    closeComm();
                }
                catch (Exception)
                {
                }
            }


        }