如何从 C# 代码确定存储在 SQL Server 中的按位代码值

Question

I want to read bitwise value stored into SQL server from C# code.

Assume that following code which stores bitwise values into database.

DECLARE @MedCopay VARCHAR(1);
DECLARE @MedDeductible VARCHAR(1);
DECLARE @MedCoins VARCHAR(1);
SET @MedCopay = 'Y';
SET @MedDeductible = 'N';
SET @MedCoins = 'Y';

SELECT CASE
       WHEN @MedCopay = 'Y'
       THEN 1
       ELSE 0
   END|CASE
           WHEN @MedDeductible = 'Y'
           THEN 10
           ELSE 0
       END|CASE
               WHEN @MedCoins = 'Y'
               THEN 100
               ELSE 0
           END;

Above query will store following value into DB

101

So question is that how can I write c# code to determine that

 101 = MedCopay & MedCoins?

Answer 1

Are you looking for enum ?

[Flags]
public enum Med {
  Copay = 1,
  Deductable = 2,
  Coins = 4
};

and so

   // 101
   Console.Write(Convert.ToString((int) (Med.Copay | Med.Coins), 2));

reverse:

  String source = "101";

  Med parsed = (Med) (Convert.ToInt32(source, 2));
  // Copay, Coins
  Console.Write(parsed);

you may want to implement an extension class for this:

  public static class MedExtensions {
    public static String Represent(this Med value) {
      return Convert.ToString((int) value, 2);
    }
  } 

And so the test will be

  Console.Write((Med.Copay | Med.Coins).Represent());