NP93 Error in Program

Thank you for your help, Scott Lysle

You need the rest of the example if you did not get it:

public class AcctNumberFormat : IFormatProvider, ICustomFormatter
{
   private const int ACCT_LENGTH = 12;

   public object GetFormat(Type formatType)
   {
      if (formatType == typeof(ICustomFormatter))
         return this;
      else
         return null;
   }

   public string Format(string fmt, object arg, IFormatProvider formatProvider)
   {
      // Convert argument to a string
      string result = arg.ToString();

      // If account number is less than 12 characters, pad with leading zeroes
      if (result.Length < ACCT_LENGTH)
         result = result.PadLeft(ACCT_LENGTH, '0');
      // If account number is more than 12 characters, truncate to 12 characters
      if (result.Length > ACCT_LENGTH)
         result = result.Substring(0, ACCT_LENGTH);  

      // Add hyphens for formatting code "H"
      if (! String.IsNullOrEmpty(fmt) && fmt.ToUpper() == "H")
         return result.Substring(0, 5) + "-" + result.Substring(5, 3) + "-" + result.Substring(8);
      // Return string representation of argument for any other formatting code
      else
         return result;
   }  
}