Simple Data Access Layer against SQL Server

//This code developed by Ramy Mahrous 
//ramyamahrous@hotmail.com
//Its contents is provided "as is", without warranty.


/// <summary>
/// Acts as Data Access Layer for SQL Server
/// </summary>
public class DataAccessLayer
{
private static string SqlConnectionString = "Integrated Security=SSPI;Persist Security Info=True;Initial Catalog=DummyDatabase;Data Source=.;Connect Timeout=200;";
//your connection string I place mine for illustration.. DON'T HARDLY WRITE IT, pass it as argument or add it in application configuration 
        /// <summary>
        /// Replaces every parameter with its value from 2D array
        /// </summary>
        /// <param name="query">Query</param>
        /// <param name="parameters">Query parameters</param>
        /// <returns>Query with parameters value to be executed against SQL Server Database</returns>
        private static string SetParametersValue(string query, string[,] parameters)
        {
            for (int i = 0; i < parameters.Length / 2; i++)
            {
                if (!string.IsNullOrEmpty(parameters[i, 0]))
                    query = query.Replace(parameters[i, 0], "'" + parameters[i, 1] + "'");
            }
            return query;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sp"></param>
        /// <returns></returns>
        public static object ExecuteScalar(string sp, CommandType commandType)
        {
            SqlConnection con = new SqlConnection(SqlConnectionString);
            SqlCommand com = new SqlCommand(sp, con);
            object result = null;

            com.CommandType = commandType;

            try
            {
                con.Open();
                result = com.ExecuteScalar();
                con.Close();
            }
            catch (System.Exception ex)
            {
                //log the exception
            }
            return result;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sp"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static object ExecuteScalar(string sp, string[,] parameters, CommandType commandType)
        {
            SqlConnection con = new SqlConnection(SqlConnectionString);
            SqlCommand com = new SqlCommand(SetParametersValue(sp, parameters), con);
            object result = null;

            
            com.CommandType = commandType;

            for (int i = 0; i < parameters.Length / 2; i++)
            {
                com.Parameters.AddWithValue(parameters[i, 0], parameters[i, 1]);
            }

            try
            {
                con.Open();
                result = com.ExecuteScalar();
                con.Close();
            }
            catch (System.Exception ex)
            {
                //log the exception
            }
            return result;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sp"></param>
        /// <returns></returns>
        public static SqlDataReader ExecuteQuery(string sp, CommandType commandType)
        {
            SqlConnection con = new SqlConnection(SqlConnectionString);
            SqlCommand com = new SqlCommand(sp, con);
            SqlDataReader reader = null;
            
            com.CommandType = commandType;

            try
            {
                con.Open();
                reader = com.ExecuteReader(CommandBehavior.CloseConnection);
            }
            catch (System.Exception ex)
            {
                //log the exception
            }
            return reader;
        }

        /// <summary>
        /// FOR SQL
        /// </summary>
        /// <param name="sp"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static SqlDataReader ExecuteQuery(string sp, string[,] parameters, CommandType commandType)
        {
            SqlConnection con = new SqlConnection(SqlConnectionString);
            SqlCommand com = new SqlCommand(SetParametersValue(sp, parameters), con);
            SqlDataReader reader = null;

            
            com.CommandType = commandType;

            for (int i = 0; i < parameters.Length / 2; i++)
            {
                com.Parameters.AddWithValue(parameters[i, 0], parameters[i, 1]);
            }

            try
            {
                con.Open();
                reader = com.ExecuteReader(CommandBehavior.CloseConnection);
            }
            catch (System.Exception ex)
            {
                //log the exception
            }
            return reader;
        }

        /// <summary>
        /// FOR SQL
        /// </summary>
        /// <param name="sp"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static void ExecuteNonQuery(string sp, CommandType commandType)
        {
            SqlConnection con = new SqlConnection(SqlConnectionString);
            SqlCommand com = new SqlCommand(sp, con);

            
            com.CommandType = CommandType.StoredProcedure;

            try
            {
                con.Open();
                com.ExecuteNonQuery();
                con.Close();
            }
            catch (System.Exception ex)
            {
                //log the exception
            }
        }

        /// <summary>
        /// FOR SQL
        /// </summary>
        /// <param name="sp"></param>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static void ExecuteNonQuery(string sp, string[,] parameters, CommandType commandType)
        {
            SqlConnection con = new SqlConnection(SqlConnectionString);
            SqlCommand com = new SqlCommand(SetParametersValue(sp, parameters), con);

            
            com.CommandType = commandType;

            for (int i = 0; i < parameters.Length / 2; i++)
            {
                com.Parameters.AddWithValue(parameters[i, 0], parameters[i, 1]);
            }

            try
            {
                con.Open();
                com.ExecuteNonQuery();
                con.Close();
            }
            catch (System.Exception ex)
            {
                //log the exception
            }
        }
    }