再談C#編碼規范

編碼規范是老生常談的問題，現在再看代碼規范可能不會再去在意變量，控件的命名方法等，而是更加關注代碼的實用性。

首先我們要明白一下幾點，

1.代碼寫出來除了讓他跑起來還有個非常非常重要的作用是維護，因為沒有一成不變的代碼，需求變化代碼就不可避免的要變化。

2.你不是一個人在寫代碼，你身后有一個團隊，這個團隊中任何一個人都有可能會改你的代碼，你如果寫的不規范，后面的人會跟着寫。舉一個例子，最初的代碼可能是這樣的，

                if (OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "CZ-SP")
                {
                    OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                    e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);
                    e = ReGetFlight.GetDirectFlightHighWeightEntity(OrderInfo.O_FlightEntity, "", e.FlightAgency);
                    e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());
                    regetFlightInitData.HighCostAndWeightEntity = e;
                    regetFlightInitData.TicketType = "0001";
                    //如果是海航,則不需要政策倒查驗證
                    regetFlightInitData.ReSearchNoFlight = false;
                }
                else
                {
                    OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                    e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());
                    e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);
                    e.CostRate1 = 1.0M;
                    regetFlightInitData.HighCostAndWeightEntity = e;
                    //如果是海航,則不需要政策倒查驗證
                    regetFlightInitData.ReSearchNoFlight = false;

                }

但是過一時間又來個需求，對於“MU-WS”也需要走上面的邏輯，你會怎么寫，如果你只是完成任務可能會像下面這樣寫

                if (OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "CZ-SP" || OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "MU-WS")
                {
                    OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                    e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);
                    e = ReGetFlight.GetDirectFlightHighWeightEntity(OrderInfo.O_FlightEntity, "", e.FlightAgency);
                    e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());
                    regetFlightInitData.HighCostAndWeightEntity = e;
                    regetFlightInitData.TicketType = "0001";
                    //如果是海航,則不需要政策倒查驗證
                    regetFlightInitData.ReSearchNoFlight = false;
                }
                else
                {
                    OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                    e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());
                    e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);
                    e.CostRate1 = 1.0M;
                    regetFlightInitData.HighCostAndWeightEntity = e;
                    //如果是海航,則不需要政策倒查驗證
                    regetFlightInitData.ReSearchNoFlight = false;

                }

如果真的這么寫你就是始作俑者，后面的人如果都和你一樣就都會朝着葫蘆畫瓢，最后代碼可能會是這樣的

                if (OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "CZ-SP" || OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "MU-WS" || OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "MU-WS" || OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "MU-SP" || OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "CZ-WS" || OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "XT-WS")
                {
                    OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                    e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);
                    e = ReGetFlight.GetDirectFlightHighWeightEntity(OrderInfo.O_FlightEntity, "", e.FlightAgency);
                    e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());
                    regetFlightInitData.HighCostAndWeightEntity = e;
                    regetFlightInitData.TicketType = "0001";
                    //如果是海航,則不需要政策倒查驗證
                    regetFlightInitData.ReSearchNoFlight = false;
                }
                else
                {
                    OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                    e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());
                    e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);
                    e.CostRate1 = 1.0M;
                    regetFlightInitData.HighCostAndWeightEntity = e;
                    //如果是海航,則不需要政策倒查驗證
                    regetFlightInitData.ReSearchNoFlight = false;

                }

看到效果了么，你需要脫一下下面的那個長條才能看到全部代碼，這就是你的“因”種下后得到的果實。所以我們需要改進，常見的改進是回車換行，保證所有的代碼都在你一眼能夠看到的范圍之內。改進后代碼如下：

                if (OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "CZ-SP" ||
                    OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "MU-WS" || 
                    OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "MU-WS" || 
                    OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "MU-SP" || 
                    OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "CZ-WS" || 
                    OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper() == "XT-WS")
                {
                    OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                    e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);
                    e = ReGetFlight.GetDirectFlightHighWeightEntity(OrderInfo.O_FlightEntity, "", e.FlightAgency);
                    e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());
                    regetFlightInitData.HighCostAndWeightEntity = e;
                    regetFlightInitData.TicketType = "0001";
                    //如果是海航,則不需要政策倒查驗證
                    regetFlightInitData.ReSearchNoFlight = false;
                }
                else
                {
                    OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                    e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());
                    e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);
                    e.CostRate1 = 1.0M;
                    regetFlightInitData.HighCostAndWeightEntity = e;
                    //如果是海航,則不需要政策倒查驗證
                    regetFlightInitData.ReSearchNoFlight = false;

是不是清爽一點，好看一點，如果你在第一次修改代碼的時候這樣寫后面的人就會跟着這樣寫，他們可能會想，前面一個人這樣寫這樣寫應該不會有問題，雖然代碼看起來有點別扭，這時候我們可以帶着鑒賞的眼光看這段代碼，如果再想一想還有更好的方法，為何不用switch呢？

                switch (OrderInfo.O_OrdersEntity.DirectFlightChannel.Trim().ToUpper())
                {
                    case "CZ-SP":
                    case "MU-SP":
                    case "XT-WS":
                        {
                            OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                            e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);

                            e = ReGetFlight.GetDirectFlightHighWeightEntity(OrderInfo.O_FlightEntity, "", e.FlightAgency);

                            e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());

                            regetFlightInitData.HighCostAndWeightEntity = e;
                            regetFlightInitData.TicketType = "0001";
                            //如果是海航,則不需要政策倒查驗證
                            regetFlightInitData.ReSearchNoFlight = false;
                            break;
                        }
                    default:
                        {
                            OrderCostAndWeightEntity e = new OrderCostAndWeightEntity();
                            e.Sendticketcity = int.Parse(ConfigurationManager.AppSettings["SendticketcityOfDirectFlights_HU"].ToString());

                            e.FlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(OrderInfo.O_OrdersEntity.DirectFlightChannel);

                            e.CostRate1 = 1.0M;

                            regetFlightInitData.HighCostAndWeightEntity = e;
                            //如果是海航,則不需要政策倒查驗證
                            regetFlightInitData.ReSearchNoFlight = false;
                            break;
                        }
                }

是不是更加簡單，如果你這樣寫，后面的人會毫不猶豫地在后面加一個case “”：因為這個是大家再熟悉不過的語法了，絲毫不用懷疑這種寫法的正確性，於是我們可以帶着欣賞的眼光來看這段代碼了。

3.要承認我們的心智就這么多，腦袋就這么大，我們既不能一目十行也不能出口成章，所以不要寫一言看不出什么意思的代碼。

以上的想法都是建立在維護別人代碼的痛苦，失落，沮喪，各種不爽，各種吐槽之上，所以代碼規范是需要我們時刻關注的，在這里自己總結一些規范，告誡自己不要做始作俑者。

 

1.一個文件中只放一個類，類名同文件名，不要在一個文件中寫好幾個類，這樣看的清楚。

2.不要在一個文件中寫多於500行的代碼，除了那些比較大的實體類。其實我還想說超過500行看起來就有點累，但是在我們的系統中超過10000行的代碼比比皆是。

3.一個方法的代碼不要超過100行，其實我想說超過50行的方法看起來就有點累。但是在我們的系統中超過200行代碼的方法比比皆是。

4.存儲過程的代碼也不要超過100行,不要在存儲過程中寫過多的業務邏輯，那是找死，但是在我們的系統中我還真他媽的見過10000多行的存儲過程，好宏偉啊！

5.避免寫超過5個參數的方法，如果有請使用一個類或者結構來傳。

6.一個方法只有一個return result; ，不要多次return結果，最好給返回結果賦值，最后return result;

7.不要給很簡單的代碼加注釋，會有噪音的，會讓人誤解的，因為你寫的大多數情況下很片面。

8.記錄日志的時候不要到處都記，有條件的情況下針對客戶一次操作（比如下單）只記錄一條日志。

 

另外再這里列舉自己對代碼做的一些改進，不足之處歡迎大家指出。

1.參數過長使用縮進

a.
                    //獲得保險策略信息
                    insuranceStrategy = InsuranceCommon.GetStrategyInsurance(appFltEntity.ProductSource.ToString(), strategyFlightAgency.ToString(), "", appFltEntity.Price.ToString(), appFltEntity.DirectFlightChannel, appFltEntity.Airline.DibitCode, appFltEntity.Flight, appFltEntity.DepartAirport.Code, appFltEntity.ArriveAirport.Code, appFltEntity.SubClass, appFltEntity.DepartTime, appFltEntity.DepartTime.Date, null);

b.
                    //獲得保險策略信息
                    insuranceStrategy = InsuranceCommon.GetStrategyInsurance(appFltEntity.ProductSource.ToString(), 
                                                                             strategyFlightAgency.ToString(), 
                                                                             "", 
                                                                             appFltEntity.Price.ToString(), 
                                                                             appFltEntity.DirectFlightChannel, 
                                                                             appFltEntity.Airline.DibitCode, 
                                                                             appFltEntity.Flight, 
                                                                             appFltEntity.DepartAirport.Code, 
                                                                             appFltEntity.ArriveAirport.Code, 
                                                                             appFltEntity.SubClass, 
                                                                             appFltEntity.DepartTime,
                                                                             appFltEntity.DepartTime.Date, 
                                                                             null);

2.if條件過長中使用縮進

a.
                if (IsDirectFlight && (this.CorpPayType == ExpenseType.OWN || this.AccountInfo.DirectOrdersQuoteMode == "I"))
                {
                    strategyFlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(appFltEntity.DirectFlightChannel);
                    //根據票台獲得票台對應的城市
                    strategyCityID = InsuranceCommon.GetFlightAgencyCity(strategyFlightAgency);
                 }

b.
                if (IsDirectFlight &&
                    (this.CorpPayType == ExpenseType.OWN ||
                    this.AccountInfo.DirectOrdersQuoteMode == "I"))
                {
                    strategyFlightAgency = InsuranceCommon.GetStrategyFlightAgencyNew(appFltEntity.DirectFlightChannel);
                    //根據票台獲得票台對應的城市
                    strategyCityID = InsuranceCommon.GetFlightAgencyCity(strategyFlightAgency);
                 }

3.使用三元表達式

a.
                        if (InsuranceInfoList != null && InsuranceInfoList.Count > 0 && InsuranceInfoList[0].GeneralDescription.Contains("e路泰康"))
                            collections.Set("IsElderCanBuyInsurance", "T");
                        else
                            collections.Set("IsElderCanBuyInsurance", "F");

b.
collections.Set("IsElderCanBuyInsurance", InsuranceInfoList != null && InsuranceInfoList.Count > 0 && InsuranceInfoList[0].GeneralDescription.Contains("e路泰康") ? "T" : "F");

4.使用藍不大表達式

a.
                        InsuranceInfoList = InsuranceInfoList.FindAll(delegate(BookingInsuranceInfo iInfo)
                        {
                            return iInfo.TypeID == "C2C30";
                        });

b.
InsuranceInfoList = InsuranceInfoList.FindAll(a => a.TypeID == "C2C30");

5.使用switch表達式，見上面。

6.使用數組包含

a.
            if (wsFlt.ProductSource == 4 && !string.IsNullOrEmpty(wsFlt.DirectFlightChannel) && (wsFlt.DirectFlightChannel.ToUpper() == "HO-WS" or wsFlt.DirectFlightChannel.ToUpper() == "ZH-WS" or wsFlt.DirectFlightChannel.ToUpper() == "XT-WS")
                && directFlightCorporationList != null && directFlightCorporationList.Count > 0 && !directFlightCorporationList.Contains(corporationid))
            {
                return false;
            }

b.
            if (wsFlt.ProductSource == 4 &&
                new List<string>() { "HO-WS", "CZ-WS", "XT-WS" }.Contains(wsFlt.DirectFlightChannel.Trim().ToUpper()) &&
                directFlightCorporationList != null && 
                directFlightCorporationList.Count > 0 &&
                !directFlightCorporationList.Contains(corporationid))
            {
                return false;
            }

可以看到代碼中也使用了縮進。

 

歡迎大家也列舉自己遇到的代碼簡潔之道。