/// <summary>
/// Query the related entities from the database that is created by
/// the DDL
/// </summary>
private static void QueryEntities()
{
using (ModelFirstContainer context = new ModelFirstContainer())
{
// Display all the Instructor and Student typed People
// entities.
foreach (var p in context.People)
{
// Check if it is an Instructor entity.
if (p is Instructor)
{
// Display the Instructor Name and Course information.
// Note: The ToStrin() methods of the Complex Types
// Name and Address have been overriden.
Console.WriteLine("Instructor {0}'s courses:", p.Name);
foreach (var c in ((Instructor)p).Courses)
{
Console.WriteLine(c.Title);
}
}
// Check if it is a Student entity.
if (p is Student)
{
// Display the Student Name and Course information.
Console.WriteLine("Student {0}'s courses and scores:",
p.Name);
foreach (var cs in ((Student)p).CourseStudents)
{
Console.WriteLine("{0} (Score:{1})",
cs.Course.Title, cs.Score);
}
}
// Display each Person's Address information.
Console.WriteLine("Address:{0}", p.Address);
Console.WriteLine();
}
}
}
/// <summary>
/// Insert new related entities into the database that is created by
/// the DDL
/// </summary>
private static void InsertEntities()
{
using (ModelFirstContainer context = new ModelFirstContainer())
{
// Create a new Department entity.
Department department = new Department
{
DepartmentID = 1,
Name = "Computer Science",
Budget = 400000,
StartDate = DateTime.Now
};
// Create a new Course entity.
// Note: Here we only use the entity reference or entity set
// to set the relationship. In EF 4.0, we can also use the
// Foreign Key properties. For detail, please see examples
// CSEFForeignKeyAssociation.
Course course1 = new Course
{
CourseID = 1001,
Title = "Operation System",
Credits = 4,
// Set the relationship to the Department entity.
Department = department
};
// Create another new Course entity.
Course course2 = new Course
{
CourseID = 1002,
Title = ".NET Framework",
Credits = 3,
// Set the relationship to the Department entity.
Department = department
};
// Create a new Instructor.
Instructor instructor1 = new Instructor
{
PersonID = 1,
// Set Complex Properties.
Name = new Name
{
FirstName = "Jialiang",
LastName = "Ge"
},
Address = new Address
{
Country = "China",
City = "Shanghai",
Zipcode = "200000"
},
HireDate = DateTime.Now,
};
// Add the relationship.
instructor1.Courses.Add(course1);
// Create another new Instructor.
Instructor instructor2 = new Instructor
{
PersonID = 2,
// Set Complex Properties.
Name = new Name
{
FirstName = "Colbert",
LastName = "Zhou"
},
Address = new Address
{
Country = "China",
City = "Shanghai",
Zipcode = "200000"
},
HireDate = DateTime.Now
};
// Add the relationship.
instructor2.Courses.Add(course2);
// Create a new Student entity.
Student student = new Student
{
PersonID = 3,
// Set Complex Properties.
Name = new Name
{
FirstName = "Lingzhi",
LastName = "Sun"
},
Address = new Address
{
Country = "China",
City = "Shanghai",
Zipcode = "200000"
},
EnrollmentDate = DateTime.Now,
Degree = 1
};
// Add the relationships.
student.CourseStudents.Add(new CourseStudent
{
Course = course1,
Score = 90
});
student.CourseStudents.Add(new CourseStudent
{
Course = course2,
Score = 95
});
try
{
// Note: We can only add the Department entity because
// all the other related entities will be added as well.
context.AddToDepartments(department);
context.SaveChanges();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}
