3. try-catch
try
{
//ToDo: your code goes here
}
catch
{
//ToDo: if something goes wrong,
//ToDo: this block of code will be executed
}
while (true)
{
Console.WriteLine("Calculation started.");
try
{
Console.Write("Enter a: ");
int a = int.Parse(Console.ReadLine());
Console.Write("Enter b: ");
int b = int.Parse(Console.ReadLine());
Console.WriteLine($"{a}/{b} = {a/b}");
}
catch
{
Console.WriteLine("Operation failed.");
}
Console.WriteLine("Would you like continue calculations? y/n");
if (Console.ReadLine().ToLower() != "y")
{
break;
}
}
Console.WriteLine("Good bye!");
4. try-catch-finally
while (true)
{
Console.WriteLine("Calculation started.");
try
{
Console.Write("Enter a: ");
int a = int.Parse(Console.ReadLine());
Console.Write("Enter b: ");
int b = int.Parse(Console.ReadLine());
Console.WriteLine($"{a}/{b} = {a/b}");
}
catch (Exception e)
{
Console.WriteLine("Operation failed. Message: {0}", e);
}
finally
{
Console.WriteLine("Current calculation completed.");
}
Console.WriteLine("Would you like continue calculations? y/n");
if (Console.ReadLine().ToLower() != "y")
{
break;
}
}
5. Your own exception type and throw keyword
class AttendanceException : Exception
{
public AttendanceException()
{
}
public AttendanceException(string message) : base(message)
{
}
public AttendanceException(string message, Exception
innerException) : base(message, innerException)
{
}
protected AttendanceException(SerializationInfo info,
StreamingContext context) : base(info, context)
{
}
}
int pupilsNumber = 0;
try
{
pupilsNumber = int.Parse(Console.ReadLine());
if (pupilsNumber == 0)
{
throw new AttendanceException("Everybody absent");
}
}
catch (AttendanceException)
{
Console.WriteLine("Lesson is ignored :(");
}
catch (Exception e)
{
Console.WriteLine(e);
}
Console.WriteLine($"{pupilsNumber} pupils here");
6. Operator overloading
class Material
{
public int Weight { get; set; }
public string Name { get; set; }
public static Material operator + (Material m1,
Material m2)
{
return new Material
{
Name = m1.Name+" and "+ m2.Name,
Weight = m1.Weight + m2.Weight
};
}
}
Material water = new Material
{
Name = "Water",
Weight = 120
};
Material salt = new Material
{
Name = "Salt",
Weight = 15
};
Material solterWater = water + salt;
Console.WriteLine($"{solterWater.Name}, {solterWater.Weight}");
7. Extension Methods
public static class IntExtensions
{
public static int Increment(this int n, int amount)
{
return n + amount;
}
}
class Program
{
static void Main(string[] args)
{
Console.WriteLine(10.Increment(3));
Console.ReadLine();
}
}
