public static void Main()
{
object b = new Giraffe();
Console.WriteLine(b is Animal); // output: True
Console.WriteLine(b.GetType() == typeof(Animal)); // output: False
Console.WriteLine(b is Giraffe); // output: True
Console.WriteLine(b.GetType() == typeof(Giraffe)); // output: True
}
public static void Main()
{
object b = new Giraffe();
Console.WriteLine("b is Animal: {0}", b is Animal);
Console.WriteLine("b.GetType() == typeof(Animal): {0}", b.GetType() == typeof(Animal));
Console.WriteLine("--------------------------------------");
Console.WriteLine("b is Giraffe: {0}", b is Giraffe);
Console.WriteLine("b.GetType() == typeof(Giraffe): {0}", b.GetType() == typeof(Giraffe));
}
static void Main(string[] args)
{
object ab = 32.1; //double
object ad = 1; //this is integer
Console.WriteLine(ab is double); // output: True
Console.WriteLine(ab is int); // output: False
Console.WriteLine(ad is int); // output: True
Console.WriteLine(ab is double); // output: false
Console.WriteLine("\n");
object b = new Base();
Console.WriteLine(b is Base); // output: True
Console.WriteLine(b is Derived); // output: False
object d = new Derived();
Console.WriteLine(d is Base); // output: True
Console.WriteLine(d is Derived); // output: True
Console.WriteLine("\n");
int i = 27;
Console.WriteLine(i is System.IFormattable); // output: True
object iBoxed = i; //when you turn something into an object class instance it is boxing
Console.WriteLine(iBoxed is int); // output: True
Console.WriteLine(iBoxed is long); // output: False
Console.WriteLine("\n");
i = 23;
iBoxed = i;
int?jNullable = 7;
if (iBoxed is int newint1 && jNullable is int newint2)
{
Console.WriteLine(newint1 + newint2); // output 30
}
if (iBoxed is double newint_1 && jNullable is int newint_2)
{
Console.WriteLine(newint_1 + newint_2); // this wont print since this if statement will fail
}
Console.WriteLine("\n");
IEnumerable <int> numbers = new[] { 10, 20, 30 };
IList <int> indexable = numbers as IList <int>;
if (indexable != null)
{
Console.WriteLine(indexable[0] + indexable[indexable.Count - 1]); // output: 40
}
double x = 1234.7;
int a = (int)x;
Console.WriteLine(a); // output: 1234,
x = 1234324324234.7;
a = (int)x;
Console.WriteLine(a); // output: -2147483648
numbers = new int[] { 10, 20, 30 };
IList <int> list = (IList <int>)numbers;
Console.WriteLine(list.Count); // output: 3
Console.WriteLine(list[1]); // output: 20
Console.WriteLine("\n");
void PrintType <T>() => Console.WriteLine(typeof(T));//this is inline method
Console.WriteLine(typeof(List <string>));
PrintType <int>();
PrintType <System.Int32>();
PrintType <Dictionary <int, char> >();
b = new Giraffe();
Console.WriteLine(b is Animal); // output: True
Console.WriteLine(b.GetType() == typeof(Animal)); // output: False
Console.WriteLine(b is Giraffe); // output: True
Console.WriteLine(b.GetType() == typeof(Giraffe)); // output: True
double d1 = 3215324324.123123;
long l1 = 432543534534543543;
List <string> list111 = new List <string> {
"323", "1"
}; //this is managed type.
Console.WriteLine(sizeof(byte)); // output: 1
Console.WriteLine(sizeof(double)); // output: 8
List <customClassSizeTest> lstTest = new List <customClassSizeTest>();
var mem1 = GC.GetTotalMemory(true);
for (int mm = 0; mm < 400; mm++)
{
lstTest.Add(new customClassSizeTest(1, 3215315, 54654654654, 32));
}
var mem2 = GC.GetTotalMemory(true);
Console.WriteLine((mem2 - mem1) + $" bytes , avg {((mem2 - mem1)/400).ToString("N0")} is the size of customClassSizeTest"); // doesnt work
}