C#中的引用类型和值类型

C#中的引用类型和值类型
1. 引用类型和值类型的分类
分类如下所示：

类别	描述
值类型	基本数据类型	有符号整型：sbyte,short,int,long
无符号长整型：byte,ushort,uint,ulong
浮点型：float,double
字符型：char
布尔型：bool
枚举类型	枚举型：enum
结构类型	结构：struct
引用类型	类	基类：System.Object
字符串：string
自定义类：class
接口	接口：interface
数组	数组：int[], string[]
委托类型	用户自定义类型：delegate

2. 值类型举例

2.1 基本数据类型

2.1.1 sbyte

sbyte sByte = 127;

2.1.2 short

short x = 5;

2.1.3 int

int x = 100;

2.1.4 long

long l = 123456;

2.1.5 byte

byte myByte = 255;

2.1.6 ushort

ushort myShort = 65535;

2.1.7 uint

uint myInt = 34567123;

2.1.8 ulong

ulong uLong = 3552525;

2.1.9 float

float f = 3.5F;

2.1.10 double

double d = 3D;

2.1.11 char

char x = ‘a’;

2.1.12 bool

bool b = true;

2.2 枚举类型

2.2.1 enum

enum Days {Sat, Sun, Mon, Tue, Wed, Thu, Fri};

2.3 结构类型

2.3.1 struct

public struct Book{

publicdecimal price;

publicstring title;

publicstring author;

}

3. 引用类型举例

3.1 接口

3.1.1 interface

interface InterfaceTest{

voidPlay();

}

class ImpClass : InterfaceTest{

voidInterfaceTest.Play(){

Console.WriteLine(“Iwant to play”);

}

static voidMain(){

ImpClassobj = new ImpClass();

obj.Play();

}

}

3.2 数组

3.2.1 int[]

class TestInt{

staticvoid Main(){

int[]array = {1,2,3,4,5};

for(inti in array){

Console.WriteLine(i);

}

}

}

3.3 委托

3.3.1 delegate

delegate double MatchAction(double num);

class DelegateTest{

staticdoule Double(double input){

returninput * 2;

}

staticvoid Main(){

MatchActionma = Double;

doublemultByTwo = ma(4.5);

Console.WriteLine(“multByTwo:{0}”,multByTwo);

}

}

3.4 类

3.4.1 Object

class ObjectTest{

public int i = 10;

}

class MainTest{

object a;

a = 1;

Console.WriteLine(a);

Console.WriteLine(a.GetType());

Console.WriteLine(a.ToString());

a = newObjectTest();

ObjectTestclassRef;

classRef =(ObjectTest)a;

Console.WriteLine(classRef.i);

}

3.4.2 string

string a = “hello”;

string b = “h”;

b +=”ello”;

Console.WriteLine(a == b);

Console.WriteLine((object)a == (object)b);

3.4.3 class

class Student{

privateint age;

privatestring name;

privateint stuNum;

publicStudent(int age, string name, int stuNum){

this.age= age;

this.name= name;

this.stuNum= stuName;

}

publicvoid Print(){

Console.WriteLine(“name:{0},age:{1}, stuNum:{2}”, name, age, stuNum);

}

}

class StuTest{

staticvoid Main(){

Studentstu1 = new Student(10, “WangLei”, 1);

Studentstu2 = new Student(12, “ZhangYuan”, 10);

stu1.Print();

stu2.Print();

}

}