protected Person(string firstName, string lastName, Hometown hometown)
{
FirstName = firstName;
LastName = lastName;
Hometown = hometown;
_regex = new Regex(_pattern);
}
/*
* Comprehension Queries
* https://learning.oreilly.com/library/view/linq-pocket-reference/9780596519247/ch01s03.html
*
* C# provides a syntatic shortcut for writing LINQ queries, called query comprehension syntax,
* or simply query syntax.
*
* A comprehnsion query always starts with a 'from' clause and end with either a 'select or group'
* clause. The 'from' clause declares an iteration variable. The compiler processes comprehension
* queries by translating them to lambda syntax this is similar to what it does to the 'foreach' statements
* translating them into calls to GetEnumerator and MoveNext. This means anything you can write in
* comprehension syntax you can also write in lambda syntax.
*/
private static void LQComprehensionQuery()
{
var employeeByState = from e in Employ.GetAllEmploy()
join h in Hometown.GetHometown()
on new { City = e.City, State = e.State }
equals
new { City = h.City, State = h.State }
select new { e.LastName, h.CityCode };
foreach (var employee in employeeByState)
{
Console.WriteLine(employee.LastName + ", " + employee.CityCode);
}
} // End LQComprehensionQuery
static void Main(string[] args)
{
var db = new PersonContext();
// SELECT * FROM People
var allPeople = db.People.ToList();
// CREATE!
var person = new Person
{
FullName = "Jerry",
HairColor = "Bald",
IsRightHanded = true,
Height = 72,
Age = 53
};
db.People.Add(person);
db.SaveChanges();
// READ
var people = db.People.ToList();
// SELECT * FROM People WHERE Age < 12
var youngins = db.People.Where(peep => peep.Age < 12);
// SELECT FullName FROM People
// WHERE HairColor = "Bald" && IsRightHanded = False
var baldLefthandedPeopleNames = db.People
.Where(w => !w.IsRightHanded && w.HairColor == "Bald")
.Select(s => s.FullName);
// UPDATING
// SELECT TOP(1) * FROM PEOPLE WHERE FullName == "Jerry"
// IN C#: using the reader, create a Person Object
var jerry = db.People.First(f => f.FullName == "Jerry");
// change the desired values
jerry.HairColor = "Brown";
// UPDATE PEOPLE SET (HairColor = "Brown") WHERE Id = Jerry.Id
db.SaveChanges();
var cities = db.Cities.ToList();
var newYork = new Hometown
{
Name = "New York",
Population = 12000000,
State = "NY"
};
db.Cities.Add(newYork);
db.SaveChanges();
jerry.HomeTown = newYork;
db.SaveChanges();
var otherJerry = db.People.First(f => f.FullName == "Jerry");
db.People.Remove(otherJerry);
}
public Developer(string firstName, string lastName, Hometown hometown, EmployeeClassification classification, Seniority seniorityLevel)
: base(firstName, lastName, hometown, classification)
{
SeniorityLevel = seniorityLevel;
}
protected Employee(string firstName, string lastName, Hometown hometown, EmployeeClassification classification)
: base(firstName, lastName, hometown)
{
Classification = classification;
}
