总结：CLR Via C#（第五章）：值类型与引用类型——装箱和拆箱
struct
class Program
{
static void Main(string[] args)
{
Point p = new Point(1, 1);
Console.WriteLine(p);
p.Change(2, 2);
Console.WriteLine(p);
object o = p;
Console.WriteLine(o);
((Point)o).Change(3, 3);
Console.WriteLine(o);
p = (Point)o;
p.Change(3, 3);
Console.WriteLine(p);
}
}
internal struct Point
{
Int32 m_x, m_y;
public Point(Int32 x, Int32 y)
{
m_x = x;
m_y = y;
}
public void Change(Int32 x, Int32 y)
{
m_x = x;
m_y = y;
}
public override string ToString()
{
return string.Format("({0},{1})", m_x, m_y);
}
}
输出：
Class
如果将Point改为Class类型，则输出：
Interface
class Program
{
static void Main(string[] args)
{
Point p = new Point(1, 1);
Console.WriteLine(p);
p.Change(2, 2);
Console.WriteLine(p);
object o = p;
Console.WriteLine(o);
((Point)o).Change(3, 3);
Console.WriteLine(o);
p = (Point)o;
p.Change(3, 3);
Console.WriteLine(p);
((IChangeBoxedPoint)p).Change(4, 4);
Console.WriteLine(p);
((IChangeBoxedPoint)o).Change(5, 5);
Console.WriteLine(o);
Console.ReadLine();
}
}
internal interface IChangeBoxedPoint
{
void Change(Int32 x, Int32 y);
}
internal struct Point:IChangeBoxedPoint
{
Int32 m_x, m_y;
public Point(Int32 x, Int32 y)
{
m_x = x;
m_y = y;
}
public void Change(Int32 x, Int32 y)
{
m_x = x;
m_y = y;
}
public override string ToString()
{
return string.Format("({0},{1})", m_x, m_y);
}
}
输出：
