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今天抽了点时间，写了一个通用的生成编号的程序！
我的生成规则为年月日+两位编号，即：yyyyMMdd+两位编号，譬如：2018101001 / 2018101002 / 2018101003
首先，一个项目中有很多表需要生成编号，譬如：产品编号，评估编号，学生学号等
下面看看我的思路，如下：
首先创建一张表，如下：
create table CM_CodeNo(Id int identity(1,1) primary key not null,CodeCate varchar(50) not null unique,--现场考察 非设计类履约评估等VersionNum TimeStamp not null,CodeYear int,CodeMonth int,CodeDay int,CodeValue varchar(20),CodeCount int,AddTime datetime default(getdate()),)
简单解读下这张表的构造：
CodeCate：编号分类，譬如：产品编号、评估编号等
VersionNum：乐观锁版本号，用于处理并发，有兴趣的可参考鄙人的博客：https://www.cnblogs.com/chenwolong/p/BF.html#4094056
CodeYear：年
CodeMonth：月
CodeDay：日
CodeCount：代表今天生产了几个编号
AddTime：生产时间
CodeValue：无效字段，没用到...
表的解读就这么多，现在来看一组存储过程：
ALTER proc [dbo].[LockCodeNoProc] --(@CodeCate nvarchar(50), @IsSuccess bit=0 output)asdeclare @currentYear as int declare @currentMonth as int declare @currentDay as int declare @count as intdeclare @CodeCount as intdeclare @flag as TimeStampdeclare @rowcount As int set @currentYear=DateName(year,GetDate()) set @currentMonth=DateName(month,GetDate()) set @currentDay=DateName(day,GetDate())begin transelect @count=count(1) from CM_Code where CodeYear=@currentYear and CodeMonth = @currentMonth and CodeDay=@currentDay and CodeCate=@CodeCateif @count=0begininsert into CM_Code(CodeCate,CodeYear,CodeMonth,CodeDay,CodeValue,CodeCount,AddTime) values(@CodeCate,@currentYear,@currentMonth,@currentDay,'',1,GETDATE())select CodeCount from CM_Code where CodeYear=@currentYear and CodeMonth = @currentMonth and CodeDay=@currentDay and CodeCate=@CodeCateendelsebeginselect @count=CodeCount,@flag=VersionNum from CM_Code where CodeYear=@currentYear and CodeMonth = @currentMonth and CodeDay=@currentDay and CodeCate=@CodeCate--waitfor delay '00:00:10' --可用于模拟并发update CM_Code set CodeCount=@count+1 where VersionNum=@flag and CodeYear=@currentYear and CodeMonth = @currentMonth and CodeDay=@currentDay and CodeCate=@CodeCateset @rowcount=@@ROWCOUNTselect CodeCount from CM_Code where CodeYear=@currentYear and CodeMonth = @currentMonth and CodeDay=@currentDay and CodeCate=@CodeCateif @rowcount>0beginset @IsSuccess=1select @IsSuccessendelsebeginset @IsSuccess=0select @IsSuccessendendcommit tran
调用这个存储过程，会返回当前分类今天生产的编号数量，
时间有限，不作过多解读，大家自行理解，
下面是C#代码：
public class GetCode { public static string GetCodeNo(Enum CodeCate) { PortalCodeModel M = new PortalCodeModel(); M = U_GetCode.GetCodeNo(CodeCate); //--模拟发生了并发，需要等待，重复请求，最大请求次数为10次 int retry = 10; while (!M.IsSuccess && retry > 0) { retry--; GetCodeNo(CodeCate); } // string code = GetCodeString(M.Result); return code; } public static string GetCodeString(int CodeCount) { string initStr = DateTime.Now.ToString("yyyyMMdd"); int initLen = initStr.Length; int Len = CodeCount.ToString().Length; int MaxLen = 10; string ling = string.Empty; int TotalLen = initLen + Len; if (TotalLen <= MaxLen) { switch (Len) { case 1:ling = initStr + "0" + CodeCount.ToString();break; default: ling = initStr + CodeCount.ToString(); break; } } return ling; } } DAL层如下：
public static PortalCodeModel GetCodeNo(Enum CodeCate) { using (DataAccessBroker broker = DataAccessFactory.Instance()) { PortalCodeModel M = new PortalCodeModel(); DataAccessParameterCollection parameters = new DataAccessParameterCollection(); parameters.AddWithValue("@CodeCate", CodeCate.ToString()); parameters.AddWithValue("@IsSuccess", ParameterDirection.ReturnValue); DataSet ds = broker.FillCommandDataSet("LockCodeNoProc", parameters); // if (ds != null && ds.Tables.Count > 0) { var Result = Convert.ToInt32(ds.Tables[0].Rows[0]["CodeCount"]); var Bol = (ds.Tables[1].Rows[0][0]).ToString(); if (Bol == "True") { M.Result = Result; M.IsSuccess = true; } else { M.Result = Result; M.IsSuccess = false; } } return M; } } 枚举层如下：
////// 各个枚举的‘值’使用表名即可 /// public enum CodeCateEnum { [Description("现场考察")] Inspection, [Description("非设计类过程评估")] EvluationPros, [Description("非设计类履约评估")] EvluationPlan, }
OK ,就这么多，太忙，就不做过多的演示了！
public class PortalCodeModel { public bool IsSuccess { get; set; } public int Result { get; set; } } 说明下：当返回 IsSuccess 为 False 时，及说明发生了并发，应执行重复请求。这里采用的方式是：重复请求十次，直至成功为止！
C# 代码执行的时候，当第一次执行存储过程，会异常，请自行处理！
谢谢！