Assign value to class

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/*
C#: The Complete Reference 
by Herbert Schildt 

Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/


// This program will not compile. 
 
class X { 
  int a; 
 
  public X(int i) { a = i; } 
} 
 
class Y { 
  int a; 
 
  public Y(int i) { a = i; } 
} 
 
public class IncompatibleRef { 
  public static void Main() { 
    X x = new X(10); 
    X x2;  
    Y y = new Y(5); 
 
    x2 = x; // OK, both of same type 
 
    x2 = y; // Error, not of same type 
  } 
}


           
          


Declaring Class Instances

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/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 */
using System;

namespace Client.Chapter_5___Building_Your_Own_Classes
{
  public class DeclaringClassInstances
  {
    static void Main(string[] args)
    {
      ClassInstantied MyClass = new ClassInstantied();
    }
  }
  class ClassInstantied
  {
    public void Display()
    {
      Console.WriteLine("Hello World");
    }
  }
}

           
          


Declaring and Defining Classes

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/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 */
using System;

namespace Client.Chapter_5___Building_Your_Own_Classes
{
  public class DeclaringandDefiningClasses
  {
    static private int MyInt = 5;
    static public int MyInt2 = 10;
    static public int[] MyIntArray;
    static private int ObjectCount = 0;
    static void Main(string[] args)
    {
      MyIntArray = new int[10];
      ObjectCount++;
    }
    public static int MyMethod(int myInt)
    {
      MyInt = MyInt + myInt;
      return MyInt;
    }
    private static long MyLongMethod(ref int myInt)
    {
      return myInt;
    }
  }
}

           
          


A simple inventory example

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/*
C#: The Complete Reference 
by Herbert Schildt 

Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/

// A simple inventory example. 
 
using System; 
using System.Collections; 
 
class Inventory { 
  string name; 
  double cost; 
  int onhand; 
 
  public Inventory(string n, double c, int h) { 
    name = n; 
    cost = c; 
    onhand = h; 
  } 
 
  public override string ToString() { 
    return 
      String.Format("{0,-10}Cost: {1,6:C}  On hand: {2}", 
                    name, cost, onhand); 
  } 
} 
 
public class InventoryList { 
  public static void Main() { 
    ArrayList inv = new ArrayList(); 
     
    // Add elements to the list 
    inv.Add(new Inventory("Pliers", 5.95, 3)); 
    inv.Add(new Inventory("Wrenches", 8.29, 2));    
    inv.Add(new Inventory("Hammers", 3.50, 4)); 
    inv.Add(new Inventory("Drills", 19.88, 8)); 
 
    Console.WriteLine("Inventory list:"); 
    foreach(Inventory i in inv) { 
      Console.WriteLine("   " + i); 
    } 
  } 
}


           
          


Using Initializers

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public class Product {
    public string make = "Ford";
    public string model = "T";
    public string color;  // default value of null
    public int yearBuilt = 1910;

    public void Start() {
        System.Console.WriteLine(model + " started");
    }

    public void Stop() {
        System.Console.WriteLine(model + " stopped");
    }
}

class MainClass {

    public static void Main() {
        Product myProduct = new Product();
        System.Console.WriteLine("myProduct.make = " + myProduct.make);
        System.Console.WriteLine("myProduct.model = " + myProduct.model);
        if (myProduct.color == null) {
            System.Console.WriteLine("myProduct.color is null");
        }
        System.Console.WriteLine("myProduct.yearBuilt = " + myProduct.yearBuilt);
    }
}

    


simulate a bank account

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using System;

public class BankAccount {
public static int nNextAccountNumber = 1000;
public int nAccountNumber;
public double dBalance;

public void InitBankAccount() {
nAccountNumber = ++nNextAccountNumber;
dBalance = 0.0;
}

public void Deposit(double dAmount) {
if (dAmount > 0.0) {
dBalance += dAmount;
}
}

public double Withdraw(double dWithdrawal) {
if (dBalance <= dWithdrawal) { dWithdrawal = dBalance; } dBalance -= dWithdrawal; return dWithdrawal; } } [/csharp]

Illustrates the use of various access modifiers

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/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy

Publisher: Sybex;
ISBN: 0782129110
*/

/*
  Example5_10.cs illustrates the use of various
  access modifiers
*/


// declare the Car class
class Car
{

  // declare the fields
  public             string make;
  protected internal string model;
  internal           string color;
  protected          int horsepower = 150;
  private            int yearBuilt;

  // define the methods
  public void SetYearBuilt(int yearBuilt)
  {
    this.yearBuilt = yearBuilt;
  }

  public int GetYearBuilt()
  {
    return yearBuilt;
  }

  public void Start()
  {
    System.Console.WriteLine("Starting car ...");
    TurnStarterMotor();
    System.Console.WriteLine("Car started");
  }

  private void TurnStarterMotor()
  {
    System.Console.WriteLine("Turning starter motor ...");
  }

}


public class Example5_10
{

  public static void Main()
  {

    // create a Car object
    Car myCar = new Car();

    // assign values to the Car object fields
    myCar.make = "Toyota";
    myCar.model = "MR2";
    myCar.color = "black";
    // myCar.horsepower = 200;  // protected field not accessible
    // myCar.yearBuilt = 1995;  // private field not accessible

    // call the SetYearBuilt() method to set the private yearBuilt field
    myCar.SetYearBuilt(1995);

    // display the values for the Car object fields
    System.Console.WriteLine("myCar.make = " + myCar.make);
    System.Console.WriteLine("myCar.model = " + myCar.model);
    System.Console.WriteLine("myCar.color = " + myCar.color);

    // call the GetYearBuilt() method to get the private yearBuilt field
    System.Console.WriteLine("myCar.GetYearBuilt() = " + myCar.GetYearBuilt());

    // call the Start() method
    myCar.Start();
    // myCar.TurnStarterMotor();  // private method not accessible

  }

}