using System;

using System.Data;

​

public class Program

{

    public static void Main(string[] args)

    {

        Object result = GetTypeDefault(DbType.Int64);

        if (result == null)

        {

            Console.WriteLine("null");

        }

        else

        {

            Console.WriteLine(result);

        }

    }

    public static Object GetTypeDefault(DbType dbDataType)

    {

        switch (dbDataType)

        {

            case DbType.Boolean:

            return false;

            case DbType.DateTime:

            return DateTime.MinValue;

            case DbType.Decimal:

            return 0m;

            case DbType.Int32:

            return 0;

            case DbType.String:

            return String.Empty;

            default:

            return null;

        }

    }

}

​