how to auto increment a column in a specific format

I realize all that but, as they can't be generated automatically, the purpose of my previous post was to show how the job codes could be generated manually and (by printing them to the console) to check that the method was working correctly.

As far as a Windows Forms application is concerned, all you need to do is to incorporate this field and method into your Form class:

   static string lastJobCode = null;

   private static string GetNextJobCode()

   {

      if (lastJobCode == null)

      {

         lastJobCode = "A-1";

         return "A-1";

      }

      int number = int.Parse(lastJobCode.Substring(2));

      string newJobCode;

      if (number < 200)

      {   

         newJobCode = lastJobCode[0] + "-" + (number + 1).ToString();

      }

      else

      {

         char jobLetter = lastJobCode[0];

         if (jobLetter < 'Z')

         { 

            jobLetter = (char)(jobLetter + 1);

            newJobCode = jobLetter + "-1";

         }

         else

         {

            // start again at A-1, say

            newJobCode = "A-1";

         }

      }

      lastJobCode = newJobCode;

      return newJobCode;

   } 

Each time you add a new customer to the database you then need to call the GetNextJobCode() method to get the job code for that customer.

When the application starts, you'll need to run a query (from Form_Load say) to get the last job code added to the database (if there is one) and then set the lastJobCode field to that value. The generation of subsequent job codes will then start from there.

using System;

class Test

{

   static string lastJobCode = null;

   private static string GetNextJobCode()

   {

      if (lastJobCode == null)

      {

         lastJobCode = "A-1";

         return "A-1";

      }

      int number = int.Parse(lastJobCode.Substring(2));

      string newJobCode;

      if (number < 200)

      {   

         newJobCode = lastJobCode[0] + "-" + (number + 1).ToString();

      }

      else

      {

         char jobLetter = lastJobCode[0];

         if (jobLetter < 'Z')

         { 

            jobLetter = (char)(jobLetter + 1);

            newJobCode = jobLetter + "-1";

         }

         else

         {

            // start again at A-1, say

            newJobCode = "A-1";

         }

      }

      lastJobCode = newJobCode;

      return newJobCode;

   } 

      

   static void Main()

   {

      for(int i = 1; i <= 600; i++)

      {

         Console.Write("{0, -8}", GetNextJobCode());

      } 

      Console.ReadKey();

   }

}

The output should be: