UserDataAccess.cs

public UserEntity DeleteUser(int userId) {

            SqlConnection oCon = null;
            SqlCommand oCmd = null;
            UserEntity user = null;

            try
            {
                oCon = _connection.openConn();
                string sqlDelete = string.Format("DELETE FROM Users WHERE usr_id = @userId");

                oCmd = new SqlCommand(sqlDelete, oCon);
                oCmd.Parameters.Add(new SqlParameter("@userId", user.usr_Id));
                oCmd.ExecuteNonQuery();

            }
            catch (Exception ex)
            {

                throw ex;
            }

            return user;
        }