C#

public class UserDAL
    {
        SQLHelper db = new SQLHelper();
        
        /// <summary>
        /// Read All User Object
        /// </summary>
        /// <returns></returns>
        public DataTable SelectAllUser()
        {
            string sql = @"SELECT [UserID],[Password],[Name],[Sex],[Phone]," +
                "[Tutor],[DptName],[College],[University]," +
                "[Major],[EnrollYear],[Cntnt] " +
                "FROM [TrainingExam].[dbo].[ExprmntUser]"; 
            return db.GetDataTable(sql);
        }
        /// <summary>
        /// Insert User into DataBase
        /// </summary>
        /// <param name="user"></param>
        /// <returns></returns>
        public int InsertUser(UserModel user)
        {
            string sql = @"INSERT INTO [TrainingExam].[dbo].[ExprmntUser] VALUES(" +
                "@UserID, @Pass, @Name, @Sex, @Phone, @Tutor, @DptName, @College, @University, @Major, @EnrollYear, @Content)";
            SqlParameter[] parameters = 
            {
                new SqlParameter("@UserID", user.UserID),
                new SqlParameter("@Pass", user.Pass),
                new SqlParameter("@Name", user.Name),
                new SqlParameter("@Sex", user.Sex),
                new SqlParameter("@Phone", user.Phone),
                new SqlParameter("@Tutor", user.Tutor),
                new SqlParameter("@DptName", user.DptName),
                new SqlParameter("@College", user.College),
                new SqlParameter("@University", user.University),
                new SqlParameter("@Major", user.Major),
                new SqlParameter("@EnrollYear", user.EnrollYear),
                new SqlParameter("@Content", user.Content)
            };
            return db.ExecuteNonQuery(sql, parameters);
        }
        /// <summary>
        /// Delete User Object
        /// </summary>
        /// <param name="user"></param>
        /// <returns></returns>
        public int DeleteUser(UserModel user)
        {
            string sql = @"DELETE FROM [TrainingExam].[dbo].[ExprmntUser] WHERE UserID=@UserID";
            SqlParameter parameter = new SqlParameter("@UserID", user.UserID);
            return db.ExecuteNonQuery(sql, parameter);
        }
        /// <summary>
        /// Update User Object
        /// </summary>
        /// <param name="user"></param>
        /// <returns></returns>
        public int UpdateUser(UserModel user)
        {
            string sql = @"UPDATE [TrainingExam].[dbo].[ExprmntUser] SET UserID=@UserID, Name=@Name, Sex=@Sex, Phone=@Phone, EnrollYear=@EnrollYear, " +
                "Tutor=@Tutor, Major=@Major, DptName=@DptName, College=@College, University=@University, Content=@Content " +
                "WHERE UserID=@UserID";
            SqlParameter[] parameters = 
            {
                new SqlParameter("@UserID", user.UserID),
                new SqlParameter("@Name", user.Name),
                new SqlParameter("@Sex", user.Sex),
                new SqlParameter("@Phone", user.Phone),
                new SqlParameter("@EnrollYear", user.EnrollYear),

                new SqlParameter("@Tutor", user.Tutor),
                new SqlParameter("@Major", user.Major),
                new SqlParameter("@DptName", user.DptName),
                new SqlParameter("@College", user.College),
                new SqlParameter("@University", user.University),
                new SqlParameter("@Content", user.Content),
                new SqlParameter("@UserID", user.UserID)
            };
            return db.ExecuteNonQuery(sql, parameters);
        }
    }