private static void NullableStructures()
{
PointVal pv;
// Console.WriteLine(pv.X); // Not initialized
PointRef pr = null;
// Console.WriteLine(pr.X); // Null Pointer Exception
PointVal?pv2 = null;
if (pv2.HasValue)
{
PointVal pv3 = pv2.Value;
Console.WriteLine(pv2.Value.X);
Console.WriteLine(pv3.X);
}
PointVal pv4 = pv2.GetValueOrDefault();
}
private static void BoxingAndUnboxing()
{
int x = 1;
object obj = x; // Boxing
int y = (int)obj; // Unboxing
double pi = 3.14;
object obj2 = pi;
// double number = (int) obj2; // Invalid Cast Exception
double number = (int)(double)obj2; // Possible workaround
Console.WriteLine(number);
var point = new PointRef();
DoSomething(point);
Console.WriteLine($"PointRef: x={point.X}, y={point.Y}");
}
private static void DoSomething(object o)
{
if (o is PointRef)
{
PointRef pr = (PointRef)o;
pr.X = 11;
pr.Y = 22;
}
PointRef pr2 = o as PointRef;
if (pr2 != null)
{
// Do Something
}
if (o is PointRef pr3)
{
// Do Something
}
}