в 15:31, 26 мая 2010

2010-05-26T15:31:53Z

Admin: 1 версия

2010-05-26T12:16:02Z

1 версия

Новая страница

==Assign values to the House object"s fields using object renerence==

<source lang="csharp">class House
{
public string make;
public string model;
public string color;
public int yearBuilt;
public void Start()
{
System.Console.WriteLine(model + " started");
}
public void Stop()
{
System.Console.WriteLine(model + " stopped");
}
}
class MainClass
{
public static void Main()
{

House myHouse;
myHouse = new House();
myHouse.make = "ABC";
myHouse.model = "Apartment";
myHouse.color = "black";
myHouse.yearBuilt = 1995;
}
}</source>

==Change the object referenced by the myHouse object reference to the object referenced by yourHouse==

<source lang="csharp">class House
{
public string make;
public string model;
public string color;
public int yearBuilt;
public void Start()
{
System.Console.WriteLine(model + " started");
}
public void Stop()
{
System.Console.WriteLine(model + " stopped");
}
}
class MainClass
{
public static void Main()
{

House myHouse;
myHouse = new House();
myHouse.Start();
myHouse.Stop();

House yourHouse = new House();
yourHouse.make = "AAA";
yourHouse.model = "VVV";
yourHouse.color = "red";
yourHouse.yearBuilt = 2000;
System.Console.WriteLine("yourHouse is a " + yourHouse.model);

System.Console.WriteLine("Assigning yourHouse to myHouse");
myHouse = yourHouse;
System.Console.WriteLine("myHouse details:");
System.Console.WriteLine("myHouse.make = " + myHouse.make);
System.Console.WriteLine("myHouse.model = " + myHouse.model);
System.Console.WriteLine("myHouse.color = " + myHouse.color);
System.Console.WriteLine("myHouse.yearBuilt = " + myHouse.yearBuilt);
}
}</source>
<pre class=codeResult>started
stopped
yourHouse is a VVV
Assigning yourHouse to myHouse
myHouse details:
myHouse.make = AAA
myHouse.model = VVV
myHouse.color = red
myHouse.yearBuilt = 2000</pre>

==Class comparison==

<source lang="csharp">using System;
class ComparingRelations
{
static void Main(string[] args)
{
int a = 12;
int b = 12;
Console.WriteLine( a == b );
Console.WriteLine( (object)a == (object)b );

string c = "hello";
string d = "hello";
Console.WriteLine( (object) c==(object) d );
ClassCompare x = new ClassCompare();
ClassCompare y;
x.val = 1;
y = x;
Console.WriteLine( x == y );
x.val = 2;
Console.WriteLine( y.val.ToString() );
}
}
class ClassCompare
{
public int val = 0;
}</source>

==Creating a House object and assigning its memory location to myHouse==

<source lang="csharp">public class House
{
public string make;
public string model;
public string color;
public int yearBuilt;
public void Start()
{
System.Console.WriteLine(model + " started");
}
public void Stop()
{
System.Console.WriteLine(model + " stopped");
}
}
class MainClass
{
public static void Main()
{

House myHouse;
myHouse = new House();
}
}</source>

==Declare a House object reference named myHouse==

<source lang="csharp">public class House
{
public string make;
public string model;
public string color;
public int yearBuilt;
public void Start()
{
System.Console.WriteLine(model + " started");
}
public void Stop()
{
System.Console.WriteLine(model + " stopped");
}
}
class MainClass
{
public static void Main()
{

House myHouse;
System.Console.WriteLine("Creating a House object and assigning its memory location to myHouse");
myHouse = new House();
}
}</source>
<pre class=codeResult>Creating a House object and assigning its memory location to myHouse</pre>

==Declare another House object reference and create another House object==

<source lang="csharp">class House
{
public string make;
public string model;
public string color;
public int yearBuilt;
public void Start()
{
System.Console.WriteLine(model + " started");
}
public void Stop()
{
System.Console.WriteLine(model + " stopped");
}
}
class MainClass
{
public static void Main()
{

House myHouse;
myHouse = new House();
myHouse.Start();
myHouse.Stop();

House yourHouse = new House();
yourHouse.make = "AQW";
yourHouse.model = "SSS";
yourHouse.color = "red";
yourHouse.yearBuilt = 2000;
System.Console.WriteLine("yourHouse is a " + yourHouse.model);
}
}</source>
<pre class=codeResult>started
stopped
yourHouse is a SSS</pre>

==Declare class fields and methods==

<OL><LI>The new operator dynamically allocates memory for an object and returns a reference to it.</LI><LI>This reference is, more or less, the address in memory of the object allocated by new.</LI><LI>This reference is then stored in a variable.</LI></OL>

<source lang="csharp">public class House
{
public string make;
public string model;
public string color;
public int yearBuilt;
public void Start()
{
System.Console.WriteLine(model + " started");
}
public void Stop()
{
System.Console.WriteLine(model + " stopped");
}
}
class MainClass
{
public static void Main()
{

House myHouse;
System.Console.WriteLine("Creating a House object and assigning its memory location to myHouse");
myHouse = new House();
}
}</source>
<pre class=codeResult>Creating a House object and assigning its memory location to myHouse</pre>

==Display the field values using object reference==

<source lang="csharp">class House
{
public string make;
public string model;
public string color;
public int yearBuilt;
public void Start()
{
System.Console.WriteLine(model + " started");
}
public void Stop()
{
System.Console.WriteLine(model + " stopped");
}
}
class MainClass
{
public static void Main()
{

House myHouse;
myHouse = new House();
myHouse.make = "ABC";
myHouse.model = "Apartment";
myHouse.color = "black";
myHouse.yearBuilt = 1995;
System.Console.WriteLine("myHouse details:");
System.Console.WriteLine("myHouse.make = " + myHouse.make);
System.Console.WriteLine("myHouse.model = " + myHouse.model);
System.Console.WriteLine("myHouse.color = " + myHouse.color);
System.Console.WriteLine("myHouse.yearBuilt = " + myHouse.yearBuilt);
}
}</source>
<pre class=codeResult>myHouse details:
myHouse.make = ABC
myHouse.model = Apartment
myHouse.color = black
myHouse.yearBuilt = 1995</pre>

==Pass reference type variable without "out" and "ref"==

<source lang="csharp">using System;
class MyClass
{
public int Val = 20;
}
class MainClass
{
static void MyMethod(MyClass myObject, int intValue)
{
myObject.Val = myObject.Val + 5;
intValue = intValue + 5;
}
static void Main()
{
MyClass myObject = new MyClass();
int intValue = 10;
Console.WriteLine("Before -- myObject.Val: {0}, intValue: {1}", myObject.Val, intValue);
MyMethod(myObject, intValue);
Console.WriteLine("After -- myObject.Val: {0}, intValue: {1}", myObject.Val, intValue);
}
}</source>
<pre class=codeResult>Before -- myObject.Val: 20, intValue: 10
After -- myObject.Val: 25, intValue: 10</pre>

==Reference an object by interface and class==

<OL><LI>You can create an interface reference variable.</LI><LI>Such a variable can refer to any object that implements its interface.</LI><LI>When you call a method on an object through an interface reference, the method is the version of the method implemented by the object.</LI></OL>

<source lang="csharp">public interface Player
{
void PlayMusic();
}
public class Student : Player
{
public void PlayMusic(){}
public void DoALittleDance(){}
}
public class MainClass
{
static void Main()
{
Student st = new Student();
Player musician = st;
musician.PlayMusic();
st.PlayMusic();
st.DoALittleDance();
}
}</source>

==Reference a static member function without using the class name==

<source lang="csharp">public class A
{
public static void SomeFunction()
{
System.Console.WriteLine( "SomeFunction() called" );
}
static void Main()
{
A.SomeFunction();
SomeFunction();
}
}</source>
<pre class=codeResult>SomeFunction() called
SomeFunction() called</pre>

==Reference equals==

<source lang="csharp">public class MyClass
{
public MyClass( )
{
}

}
public class MainClass
{
static void Main()
{
MyClass referenceA = new MyClass( );
MyClass referenceB = new MyClass( );
System.Console.WriteLine( "Result of Equality is {0}", referenceA == referenceB );
}
}</source>
<pre class=codeResult>Result of Equality is False</pre>

==Reference one object by multiple interfaces==

<source lang="csharp">using System;
interface Interface1 {
void PrintOut(string s);
}
interface Interface2 {
void PrintOut(string s);
}
class MyClass : Interface1, Interface2
{
public void PrintOut(string s)
{
Console.WriteLine(s);
}
}
class MainClass
{
static void Main()
{
MyClass mc = new MyClass();
Interface1 ifc1 = (Interface1)mc;
Interface2 ifc2 = (Interface2)mc;
mc.PrintOut("object.");
ifc1.PrintOut("interface 1.");
ifc2.PrintOut("interface 2.");
}
}</source>
<pre class=codeResult>object.
interface 1.
interface 2.</pre>

==Reference type equals: complex number==

<source lang="csharp">public class ComplexNumber
{
public ComplexNumber( int real, int imaginary )
{
this.real = real;
this.imaginary = imaginary;
}
public override bool Equals( object obj )
{
ComplexNumber other = obj as ComplexNumber;
if( other == null )
{
return false;
}
return (this.real == other.real) && (this.imaginary == other.imaginary);
}
public override int GetHashCode()
{
return (int) real ^ (int) imaginary;
}
public static bool operator==( ComplexNumber me, ComplexNumber other )
{
return Equals( me, other );
}
public static bool operator!=( ComplexNumber me, ComplexNumber other )
{
return Equals( me, other );
}

private double real;
private double imaginary;
}
public class MainClass
{
static void Main()
{
ComplexNumber referenceA = new ComplexNumber( 1, 2 );
ComplexNumber referenceB = new ComplexNumber( 1, 2 );
System.Console.WriteLine( "Result of Equality is {0}",referenceA == referenceB );
System.Console.WriteLine( "Identity of references is {0}",(object) referenceA == (object) referenceB );
System.Console.WriteLine( "Identity of references is {0}",ReferenceEquals(referenceA, referenceB) );
}
}</source>
<pre class=codeResult>Result of Equality is True
Identity of references is False
Identity of references is False</pre>

==Use interface as reference==

<source lang="csharp">using System;
interface Interface1
{
void PrintOut(string s);
}
class MyClass : Interface1
{
public void PrintOut(string s)
{
Console.WriteLine("Calling through: {0}", s);
}
}
class MainClass
{
static void Main()
{
MyClass mc = new MyClass();
mc.PrintOut("object.");
Interface1 ifc = (Interface1)mc;
ifc.PrintOut("interface.");
}
}</source>
<pre class=codeResult>Calling through: object.
Calling through: interface.</pre>

← Предыдущая	Версия 15:31, 26 мая 2010
(нет различий)

Csharp/CSharp Tutorial/Class/Object Reference - История изменений

в 15:31, 26 мая 2010

Admin: 1 версия