public Student GetStudent(int studentId) { // Since EF will give us a Student object, lets return it Student student = null; // Instead of opening a connection, we just initialize the context using (var context = new SchoolContext()) { // We can use LINQ to get the first student that has a matching Id student = context.Students.First(s => s.Id == studentId); } return student; }
public List<Student> GetStudentList() { // Since EF will give us a list of Students, lets return it List<Student> studentList; // Instead of opening a connection, we just initialize the context using (var context = new SchoolContext()) { // We can use the ToList method to return an entire list of students studentList = context.Students.ToList(); } return studentList; }
// Since EF knows to look for a connection string with the same name as the context, // we can specify the connection string in our application config file (app.config) public int AddStudent(string studentName) { // Instead of opening a connection, we just initialize the context using (var context = new SchoolContext()) { // Lets create a new Student entity to add Student student = new Student() { Name = studentName }; // Adding a new Student object to the SchoolContext.Students collection creates a new record context.Students.Add(student); // Our new record isn't actually saved to the database until SchoolContext.SaveChanges is called return context.SaveChanges(); } }
static void Main(string[] args) { Console.WriteLine("hello world. This is Entity framework."); using (var ctx = new SchoolContext()) { // ctx.Database.Initialize(false); Student s = new Student(); Console.Write("Enter Student Details"); Console.Write("Name: "); s.Name = Console.ReadLine().ToString(); Console.Write("Phone: "); s.Phone = Console.ReadLine().ToString(); Console.Write("Address: "); s.Address = Console.ReadLine().ToString(); Console.Write("Course: "); s.Course = Console.ReadLine().ToString(); Console.Write("Description: "); s.Description = Console.ReadLine().ToString(); s.DateOfBirth= new DateTime(1990,12,01); ctx.Students.Add(s); ctx.SaveChanges(); var query = from st in ctx.Students orderby st.Name select st; Console.WriteLine("Students in Student context"); foreach (var item in query) { Console.WriteLine(item.Name); } Console.ReadLine(); } }