Order number generation rules, who knows with whom

1 class Program2     {3         //The order Number data source, in the actual project, is read from the database .4         string[] Strlist = {"201512000001","201512000002","201512000003","201512000004", 5                              "201512000008","201512000007","201512000006","201512000005", 6                              "201512000009","201512000010","201512000011","201512000012",7                              "201512000013","201512000014","201512000015" }; 8         Static voidMain (string[] args)9         {TenProgram P =NewProgram (); One Console.WriteLine (P.getordernum ()); A Console.readkey (); -         } -  the          Public stringGetordernum () -         { -             stringresult ="";  -             stringYearmonth = DateTime.Now.ToString ("yyyymm"); +             varCount = count (Yearmonth);//201512 5 -result = Yearmonth +"0000001"; +             varDD =count. ToString (). Length; A             Switch(DD) at             { -                  Case 1: -result = Yearmonth +"00000"+ (Count +1); -                      Break; -                  Case 2: -result = Yearmonth +"0000"+ (Count +1); in                      Break; -                  Case 3: toresult = Yearmonth +" the"+ (Count +1); +                      Break; -                  Case 4: theresult = Yearmonth +"xx"+ (Count +1); *                      Break; $                  Case 5:Panax Notoginsengresult = Yearmonth +"0"+ (Count +1); -                      Break; the                 default: +result = Yearmonth + (count +1); A                      Break; the             } +             returnresult; -         } $          $          Public intCount (stringyearmonth) { -             intresult =0; -result = Strlist.count (item=>item. Contains (Yearmonth)); the             returnresult; -         }       Wuyi}

Who has a better build rule, might as well discuss the next

Order number generation rules, who knows with whom