/*
A Programmer's Introduction to C# (Second Edition)
by Eric Gunnerson

Publisher: Apress  L.P.
ISBN: 1-893115-62-3
*/

// 04 - Exception HandlingUser-Defined Exception Classes
// copyright 2000 Eric Gunnerson
using System;

public class UserDefinedExceptionClasses
{
    public static void Main()
    {
        Summer summer = new Summer();
        try
        {
            summer.DoAverage();
        }
        catch (CountIsZeroException e)
        {
            Console.WriteLine("CountIsZeroException: {0}", e);
        }
    }
}
public class CountIsZeroException: ApplicationException
{
    public CountIsZeroException()
    {
    }
    public CountIsZeroException(string message)
    : base(message)
    {
    }
    public CountIsZeroException(string message, Exception inner)
    : base(message, inner)
    {
    }
}
public class Summer
{
    int    sum = 0;
    int    count = 0;
    float    average;
    public void DoAverage()
    {
        if (count == 0)
        throw(new CountIsZeroException("Zero count in DoAverage"));
        else
        average = sum / count;
    }
}

           
          

   


using System;

public class ExceptionHierarchyOutOfRangeException
{
    static int Zero = 0;
    static void AFunction()
    {
        try
        {
            int j = 22 / Zero;
        }
       // this exception doesn't match
        catch (ArgumentOutOfRangeException e)
        {
            Console.WriteLine("OutOfRangeException: {0}", e);
        }
        Console.WriteLine("In AFunction()");
    }
    public static void Main()
    {
        try
        {
            AFunction();
        }
        // this exception doesn't match
        catch (ArgumentException e)
        {
            Console.WriteLine("ArgumentException {0}", e);
        }
    }
}
           
          

   


using System;

public class ExceptionHierarchyNeverExecuted
{
    static int Zero = 0;
    static void AFunction()
    {
        int j = 22 / Zero;
        Console.WriteLine("In AFunction()");
    }
    public static void Main()
    {
        try
        {
            AFunction();
        }
        catch (DivideByZeroException e)
        {
            Console.WriteLine("DivideByZero {0}", e);
        }
    }
}
           
          

   


using System;


public class ExceptionHierarchy
{
    static int Zero = 0;
    public static void Main()
    {
        try
        {
            int j = 22 / Zero;
        }
        // catch a specific exception
        catch (DivideByZeroException e)
        {
            Console.WriteLine("DivideByZero {0}", e);
        }
        // catch any remaining exceptions
        catch (Exception e)
        {
            Console.WriteLine("Exception {0}", e);
        }
    }
}
           
          

   

/*
C#: The Complete Reference 
by Herbert Schildt 

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

// Using checked and unchecked with statement blocks. 
 
using System; 
 
public class CheckedBlocks {  
  public static void Main() {  
    byte a, b; 
    byte result; 
 
    a = 127; 
    b = 127; 
  
    try {  
      unchecked { 
        a = 127; 
        b = 127; 
        result = unchecked((byte)(a * b)); 
        Console.WriteLine("Unchecked result: " + result); 
 
        a = 125; 
        b = 5; 
        result = unchecked((byte)(a * b)); 
        Console.WriteLine("Unchecked result: " + result); 
      } 
 
      checked { 
        a = 2; 
        b = 7; 
        result = checked((byte)(a * b)); // this is OK 
        Console.WriteLine("Checked result: " + result); 
 
        a = 127; 
        b = 127; 
        result = checked((byte)(a * b)); // this causes exception 
        Console.WriteLine("Checked result: " + result); // won't execute 
      } 
    }  
    catch (OverflowException exc) {  
      // catch the exception  
      Console.WriteLine(exc); 
    }  
  }  
}


           
          

   
 

using System;

public class ConstructorException : Exception {

    public ConstructorException(object origin)
        : this(origin, null) {
    }

    public ConstructorException(object origin, Exception innerException)
        : base("Exception in constructor", innerException) {
        prop_Typename = origin.GetType().Name;
        prop_Time = DateTime.Now.ToLongDateString() + " " +
            DateTime.Now.ToShortTimeString();
    }

    protected string prop_Typename = null;
    public string Typename {
        get {
            return prop_Typename;
        }
    }

    protected string prop_Time = null;
    public string Time {
        get {
            return prop_Time;
        }
    }
}
public class Starter {
    public static void Main() {
        try {
            MyClass obj = new MyClass();
        } catch (ConstructorException except) {
            Console.WriteLine(except.Message);
            Console.WriteLine("Typename: " + except.Typename);
            Console.WriteLine("Occured: " + except.Time);
        }
    }
}

class MyClass {
    public MyClass() {
        // initialization fails
        throw new ConstructorException(this);
    }
}

    

   

/*
C#: The Complete Reference 
by Herbert Schildt 

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

// Using checked and unchecked. 
 
using System; 
 
public class CheckedDemo {  
  public static void Main() {  
    byte a, b; 
    byte result; 
 
    a = 127; 
    b = 127; 
  
    try {  
      result = unchecked((byte)(a * b)); 
      Console.WriteLine("Unchecked result: " + result); 
 
      result = checked((byte)(a * b)); // this causes exception 
      Console.WriteLine("Checked result: " + result); // won't execute 
    }  
    catch (OverflowException exc) {  
      // catch the exception  
      Console.WriteLine(exc); 
    }  
  }  
}