static void Main() { StudentsDirectory database1 = new StudentsDirectory(); SpecialtiesDirectory database2 = new SpecialtiesDirectory(); // LINQ query var joinedData = from student in database1.Students orderby student.FirstName ascending, student.LastName ascending join speciality in database2.StudentSpecialties on student.FacultyNumber equals speciality.FacultyNumber select new { student.FirstName, student.LastName, student.FacultyNumber, speciality.Speciality }; // lambda expression var joinedDataLinqExtMtd = database1.Students.OrderBy(st => st.FirstName) .ThenBy(st => st.LastName) .Join(database2.StudentSpecialties, st => st.FacultyNumber, sp => sp.FacultyNumber, (student, speciality) => new { student.FirstName, student.LastName, student.FacultyNumber, speciality.Speciality }); // printing Console.WriteLine("{0, -18} {1, -8} {2, -12}", "Name", "FacNum", "Specialty"); foreach (var item in joinedData) { Console.WriteLine("{0, -18} {1, -8} {2, -12}", item.FirstName + " " + item.LastName, item.FacultyNumber, item.Speciality); } }
public static List <StudentWithGroup> CreateGroupsDirectory() { var studentsWithGroups = new List <StudentWithGroup>(); // using the intitial students databae, to create new studets with groups database StudentsDirectory database = new StudentsDirectory(); foreach (var student in database.Students) { if (student.GroupNumber == 1) { studentsWithGroups.Add(new StudentWithGroup(student, "C#")); } else if (student.GroupNumber == 2) { studentsWithGroups.Add(new StudentWithGroup(student, "PHP")); } else if (student.GroupNumber == 3) { studentsWithGroups.Add(new StudentWithGroup(student, "JS")); } else if (student.GroupNumber == 4) { studentsWithGroups.Add(new StudentWithGroup(student, "Java")); } else { studentsWithGroups.Add(new StudentWithGroup(student, "No group chosen")); } } return(studentsWithGroups); }
static void Main() { // creating an instance of the StudentsDirectory class, so that we can use its IList<Student> StudentsDirectory database = new StudentsDirectory(); // running LINQ query var studentsByPhoneQuery = database.Students.StudentsByPhoneQuery(); // printing - by invoking the PrintStudentsInfo() method from the StudentsByFirstAndLastName project StudentsByFirstAndLastName.PrintStudentsInfo(studentsByPhoneQuery); }
static void Main() { // creating an instance of the StudentsDirectory class, so that we can use its IList<Student> StudentsDirectory database = new StudentsDirectory(); // running LINQ query var studentsByNames = database.Students.StudentsByNames(); // printing PrintStudentsInfo(studentsByNames); }
static void Main() { // creating an instance of the StudentsDirectory class, so that we can use its IList<Student> StudentsDirectory database = new StudentsDirectory(); // running LINQ query var studentsByGroupQuery = from student in database.Students orderby student.FirstName group student by student.GroupNumber into studentGroup where studentGroup.Key == 2 select studentGroup; // printing PrintStudentInfoByGroup(studentsByGroupQuery); }
static void Main() { // creating an instance of the StudentsDirectory class, so that we can use its IList<Student> StudentsDirectory database = new StudentsDirectory(); // running LINQ query var excellentStudents = from student in database.Students where student.Marks.Contains(6) select new { Fullname = string.Join(" ", student.FirstName, student.LastName), Marks = string.Join(", ", student.Marks) }; // printing foreach (var student in excellentStudents) { Console.WriteLine("Name: {0}, Grades: {{{1}}}", student.Fullname, student.Marks); } }
static void Main() { // creating an instance of the StudentsDirectory class, so that we can use its IList<Student> StudentsDirectory database = new StudentsDirectory(); // using lambda expressions var sortedStudents = database.Students.OrderByDescending(student => student.FirstName).ThenBy(student => student.LastName); // running LINQ query var studentsSortQuery = database.Students.StudentsSortQuery(); // printing - by invoking the PrintStudentsInfo() method from the StudentsByFirstAndLastName project StudentsByFirstAndLastName.PrintStudentsInfo(sortedStudents); Console.WriteLine(); StudentsByFirstAndLastName.PrintStudentsInfo(studentsSortQuery); }
static void Main() { // creating an instance of the StudentsDirectory class, so that we can use its IList<Student> StudentsDirectory database = new StudentsDirectory(); // running LINQ query var studentsByAgeQuery = from student in database.Students where student.Age >= 18 && student.Age <= 24 select new { student.FirstName, student.LastName, student.Age }; // limiting the query to names and age // printing foreach (var student in studentsByAgeQuery) { Console.WriteLine("Name: {0} {1}, Age: {2}", student.FirstName, student.LastName, student.Age); } }