C#

public class UserBLL
    {
        private UserDAL userdal = new UserDAL();

        /// <summary>
        /// Get All User Information
        /// </summary>
        /// <returns></returns>
        public DataTable GetAllUser()
        {
            return userdal.SelectAllUser();
        }
        /// <summary>
        /// Add User Information
        /// </summary>
        /// <param name="user"></param>
        /// <returns></returns>
        public bool AddUser(UserModel user)
        {
            if (userdal.InsertUser(user) > 0)
                return true;
            else
                return false;
        }
        /// <summary>
        /// Delete User Information
        /// </summary>
        /// <param name="user"></param>
        /// <returns></returns>
        public bool DeleteUser(UserModel user)
        {
            if (userdal.DeleteUser(user) > 0)
                return true;
            else
                return false;
        }
        /// <summary>
        /// Update User Information
        /// </summary>
        /// <param name="user"></param>
        /// <returns></returns>
        public bool UpdateUser(UserModel user)
        {
            if (userdal.UpdateUser(user) > 0)
                return true;
            else
                return false;
        }
    }

public class UserModel
    {
        public string UserID
        {
            get;
            set;
        }

        public string Name
        {
            get;
            set;
        }

        public string Sex
        {
            get;
            set;
        }

        public string DptName
        {
            get;
            set;
        }

        public string Phone
        {
            get;
            set;
        }

        public string Major
        {
            get;
            set;
        }

        public string University
        {
            get;
            set;
        }

        public string Tutor
        {
            get;
            set;
        }

        public string EnrollYear
        {
            get;
            set;
        }

        public string College
        {
            get;
            set;
        }

        public string Content
        {
            get;
            set;
        }

        public string Pass
        {
            get;
            set;
        }
    }

private IDbConnection CreateConnection()
{
    return new SqlConnection("YOUR CONNECTION STRING HERE");
}

public IEnumerable<UserModel> SelectAllUser()
{
    const string sql = @"SELECT [UserID], [Password], [Name], [Sex], [Phone]," 
        + "[Tutor], [DptName], [College], [University]," 
        + "[Major], [EnrollYear], [Cntnt] " 
        + "FROM [TrainingExam].[dbo].[ExprmntUser]"; 
    
    using (var connection = CreateConnection())
    {
        return connection.Query<UserModel>(sql);
    }
}

public int InsertUser(UserModel user)
{
    const string sql = @"INSERT INTO [TrainingExam].[dbo].[ExprmntUser] VALUES ("
        + "@UserID, @Pass, @Name, @Sex, @Phone, @Tutor, @DptName, @College, @University, @Major, @EnrollYear, @Content)";
    
    using (var connection = CreateConnection())
    {
        return connection.Execute(sql, user);
    }
}

public int DeleteUser(UserModel user)
{
    const string sql = @"DELETE FROM [TrainingExam].[dbo].[ExprmntUser] WHERE UserID = @UserID";
    
    using (var connection = CreateConnection())
    {
        return connection.Execute(sql, user);
    }
}

public int UpdateUser(UserModel user)
{
    const 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";
    
    using (var connection = CreateConnection())
    {
        return connection.Execute(sql, user);
    }
}

Jean-Pierre Bachmann wrote:

Don't mention that the uint takes less memory but this is not the point.

Jean-Pierre Bachmann wrote:

Don't mention that the uint takes less memory

int:  -2147483648 to 2147483647
uint:           0 to 4294967295

ushort test;
int test2 = 10000000;
test = (ushort)test2;

Jean-Pierre Bachmann wrote:

Don't mention that the uint takes less memory but this is not the point.

Jean-Pierre Bachmann wrote:

This is absolute bad from my point of view. .... So why are thees value types not used that often?