public void EndEdit()
{
using (new Log())
{
backup = ToImmutable();
}
}
// 初始化
public void Initial()
{
// 方式1
var person = new Person();
// 方式二
Person p = new();
string firstName = "marson";
string lastName = "shine";
var ps = new Person {
FirstName = firstName,
LastName = lastName
};
var ps2 = new Person {
FirstName = firstName,
LastName = lastName
};
// record 类型，常用语只读场景，表示不可变类型
ImmutablePerson ip = new(firstName, lastName);
ImmutablePerson ip2 = new(firstName, lastName);
Console.WriteLine($"FullName = {ip.FirstName} {ip.LastName}");
Console.WriteLine($"record 类型比较 ip == ip2 : {ip == ip2}");
Console.WriteLine($"record 类型比较 ip.HashCode() = {ip.GetHashCode()}; ip2.HashCode() = {ip2.GetHashCode()}; 相等性 : {ip.GetHashCode() == ip2.GetHashCode()}");
ImmutablePerson ip3 = ip2;
ip3.FirstName = "summer";
Console.WriteLine($"ip2.FirstName = {ip2.FirstName} ip3.FirstName = {ip3.FirstName}");
Console.WriteLine($"record 类型比较 ip.HashCode() = {ip.GetHashCode()}; ip2.HashCode() = {ip2.GetHashCode()}; 相等性 : {ip.GetHashCode() == ip2.GetHashCode()}");
// class 类型比较
Person p1 = new() { FirstName = "marsonshine", LastName = "shine" };
Person p2 = new() { FirstName = "marsonshine", LastName = "shine" };
Console.WriteLine($"class 类型比较 p1 == p2 : {p1 == p2}");
Console.WriteLine($"class 类型比较 ps.HashCode() = {ps.GetHashCode()}; ps2.HashCode() = {ps2.GetHashCode()}; 相等性 : {ps.GetHashCode() == ps2.GetHashCode()}");
// record 上的 with 关键字
// 可以指定属性必须和选填，在构造函数参数体现是必填
// 选填是跟以前属性写法一样
// 如果你想在原来的类型下对增加一些属性值，或者更改某些属性值，但是又不想破坏 record 带来的数据不变性，这个时候我们就可以使用 with 关键字，它会从已有的 record 类型按值复制出来一个新的 record 类型
LoginResource login = new("MarsonShine", "123$%^") { RememberMe = true };
LoginResource loginLowercased = login with {
UserName = login.UserName.ToLowerInvariant()
};
Console.WriteLine(login);
Console.WriteLine(loginLowercased);
var weight = 200;
WeightMeasurement measurement = new(DateTime.Now, weight) {
Pounds = WeightMeasurement.GetPounds(weight)
};
}
}
public class Person {
public void _01()
{
// object-initializer 中可以对 init-only property 赋值
var person01 = new ImmutablePerson
{
FirstName = "luo",
LastName = "tao",
};
// constructor 中可以对 init-only property 赋值
var person02 = new ImmutablePerson("luo", "tao");
// CS8852 init-only property 不能再被赋值
// person01.FirstName = "owen";
}
public void TestCreateImmutablePerson()
{
var expected =
"{\"FirstName\":\"John\",\"LastName\":\"Petersen\",\"Schools\":[{\"Institution\":\"Mansfield\",\"Year\":\"1988\",\"Degree\":\"BS\"},{\"Institution\":\"St. Joseph's\",\"Year\":\"1993\",\"Degree\":\"MBA\"},{\"Institution\":\"Rutgers\",\"Year\":\"2004\",\"Degree\":\"JD\"}]}";
var schools = new List <ImmutableSchool>()
{
new ImmutableSchool()
{
Degree = "BS", Institution = "Mansfield", Year = "1988"
},
new ImmutableSchool()
{
Degree = "MBA", Institution = "St. Joseph's", Year = "1993"
},
new ImmutableSchool()
{
Degree = "JD", Institution = "Rutgers", Year = "2004"
}
};
var person = new ImmutablePerson()
{
FirstName = "John", LastName = "Petersen", Schools = schools.ToImmutableArray()
};
var actual = JsonConvert.SerializeObject(person);
Assert.AreEqual(expected, actual);
person.Schools = new ImmutableArray <ImmutableSchool>();
Assert.AreEqual(3, person.Schools.Value.Length);
person.Schools.Value[0].Degree = "XX";
Assert.AreEqual("BS", person.Schools.Value[0].Degree);
var x = new ImmutableArray <ImmutableSchool>();
}
static void Main(string[] args)
{
var jeff = new ImmutablePerson {
FirstName = "Jeff",
LastName = "Winger"
};
// jeff.FirstName = "Geoff";
var car = new ImmutableVehicle {
Brand = "Mazda MX-5 RF",
Color = "Soul Red Crystal Metallic",
Wheels = 4
};
var repaintCar = car with {
Color = "Polymetal Grey Metallic"
};
WriteLine("Original color was {0}, new color is {1}.",
arg0: car.Color, arg1: repaintCar.Color);
var oscar = new ImmutableAnimal("Oscar", "Labrador");
var(who, what) = oscar; // calls deconstruct method
WriteLine($"{who} is a {what}.");
}
void UsingPacktLib9()
{
object[] passengers =
{
new FirstClassPassenger {
AirMiles = 1_419
},
new FirstClassPassenger {
AirMiles = 16_562
},
private static void RunRecordsDemo()
{
// work with records
var pavel =
new ImmutablePerson
{
FirstName = "Pavel",
LastName = "Talochka"
};
//init exception, Has to intialize when object create
// pavel.FirstName = "Michail";
var car = new ImmutableVehicle
{
Brand = "BMW",
Color = "Soul Red Crystal Metallic",
Wheels = 4
};
// cloning object
var repaintingCar = car with {
Color = "Pink"
};
WriteLine("Original color of the car is {0}, new color is {1}",
arg0: car.Color,
arg1: repaintingCar.Color);
// immutable animal example
var oscar = new ImmutableAnimal("Oscar", "Labrador");
var(who, what) = oscar;
WriteLine("{0} is a {1}.",
arg0: who,
arg1: what);
}
static void Main(string[] args)
{
Person Olli = new("Olli", new DateTime(1983, 12, 17));
// ------------------------ page 180 - Record short version ------------------------
var kosto = new ImmutableAnimal("Kosto", "Cat");
var(name, species) = kosto;
System.Console.WriteLine($"{name} is a {species}.");
// ------------------------ page 179 - Init / Records ------------------------
var Lenchen = new ImmutablePerson
{
FirstName = "Magdalena",
LastName = "Bergmann"
};
var car = new ImmutableVehicle
{
Wheels = 4,
Brand = "Ford",
Color = "Blue",
};
var repaintedCar = car with {
Color = "Black"
};
// repaintedCar.Color = "Green";
System.Console.WriteLine($"Original color was {car.Color}, repainted color is {repaintedCar.Color}.");
// ------------------------ page 176 - Pattern Matching ------------------------
/*
* object[] passengers = {
* new FirstClassPassenger(){ AirMiles = 1_415},
* new FirstClassPassenger{ AirMiles = 16_562},
* new CoachClassPassenger{ CarryOnKG = 25.3},
* new CoachClassPassenger{ CarryOnKG = 0.3},
* new BusinessClassPassenger(),
* };
*
* foreach (object passenger in passengers)
* {
* decimal fligthCost = passenger switch
* {
* FirstClassPassenger p => p.AirMiles switch
* {
* > 35000 => 1500M,
* > 15000 => 1750M,
* _ => 2000M,
* },
*
* BusinessClassPassenger => 1000M,
*
* CoachClassPassenger p when p.CarryOnKG < 10.0 => 500M,
* CoachClassPassenger => 650M,
* _ => 800M,
* };
*
* System.Console.WriteLine($"Flight costs {fligthCost:C} for {passenger}");
* }
* //*/
// ------------------------ page 172 - Properties and Indexers ------------------------
/*
* System.Console.WriteLine(Olli.Origin);
* System.Console.WriteLine(Olli.Age);
* try
* {
* Olli.FavoritPrimaryColor = "yello";
*
* }
* catch (Exception e)
* {
* System.Console.WriteLine(e.Message);
* }
* System.Console.WriteLine(Olli.FavoritPrimaryColor);
*
* Olli.Children.Add(new Person("child1"));
* Olli.Children.Add(new Person("child2"));
* Olli.Children.Add(new Person("child3"));
* System.Console.WriteLine(Olli.Children[4]);
*/
// ------------------------ page 167 - parameter passing ------------------------
/*
* int a = 10;
* int b = 20;
* int c = 30;
* System.Console.WriteLine($"Before: a = {a}, b = {b}, c = {c}");
* Olli.PassingParameters(a, ref b, out c);
* System.Console.WriteLine($"After: a = {a}, b = {b}, c = {c}");
*/
// ------------------------ page 165 - method overloading ------------------------
// System.Console.WriteLine(Olli.SayHello("Lena"));
// ------------------------ page 162 - tuple / deconstruct tuple ------------------------
(string, int)fruits = Olli.GetFruit();
/*
* System.Console.WriteLine($"There are {fruits.Item2} {fruits.Item1} ");
* // Deconstruct tuple
* (string fruit, int amount) = Olli.GetFruit();
* System.Console.WriteLine($"{fruit}, {amount}");
*
* var fruitNamed = Olli.GetNamedFruit();
* System.Console.WriteLine($"There are {fruitNamed.Numbers} {fruitNamed.Name}");
*/
// ------------------------ page 158 - default ------------------------
ThingOfDefaults defaultThing = new();
//System.Console.WriteLine(defaultThing);
// ------------------------ page 157 - constructor ------------------------
Person Sigi = new("Sigi", new DateTime(2018, 09, 07));
//System.Console.WriteLine(Sigi.ToString());
// ------------------------ page 156 - const / read-only ------------------------
//System.Console.WriteLine($"{Olli.Name} is a {Person.Species}");
// ------------------------ page 155 - static ------------------------
BankAccount.InterestRate = 0.012M;
var lenasAccount = new BankAccount();
lenasAccount.accountName = "Lenas Account";
lenasAccount.Balance = 5500;
//System.Console.WriteLine(format: "{0} earned {1:C} interest.", arg0: lenasAccount.accountName, arg1: lenasAccount.Balance * BankAccount.InterestRate);
// ------------------------ page 150 - basics ------------------------
Person Lena = new();
Lena.Name = "Lena";
Lena.favoriteWonder = WondersOfTheAncientWorld.LighthouseOfAlexandria;
Lena.DateOfBirth = new DateTime(1986, 09, 07);
Person Sigggi = new Person {
Name = "Sigi", DateOfBirth = new DateTime(2019, 12, 24), favoriteWonder = (WondersOfTheAncientWorld).3
};
Lena.Children.Add(new Person {
Name = "child1"
});
Lena.Children.Add(new Person()
{
Name = "child2"
});
/*
* Console.WriteLine(
* format: "{0} was born on {1:dddd, d MMMM yyyy} and likes {2} (int of wonder: ). ",
* arg0: Lena.name,
* arg1: Lena.dateOfBirth,
* arg2: Lena.favoriteWonder);
*
* Console.WriteLine(
* format: "{0} came to us on {1: dd MMM yy} and likes {2}",
* arg0: Sigi.name,
* arg1: Sigi.dateOfBirth,
* arg2: Sigi.favoriteWonder);
*
* foreach (var child in Lena.children) {
* System.Console.WriteLine(child.name);
* }
*/
}
}