📅 最后修改于: 2021-05-29 21:14:14 🧑 作者: Mango
装箱和拆箱是C＃中的重要概念。 C＃类型系统包含三种数据类型：值类型(int，char等) ，引用类型(对象)和指针类型。基本上，它将值类型转换为引用类型，反之亦然。装箱和拆箱可实现类型系统的统一视图，在该系统中，任何类型的值都可以视为对象。
| Boxing |
Unboxing |
| It convert value type into an object type. |
It convert an object type into value type. |
| Boxing is an implicit conversion process. |
Unboxing is the explicit conversion process. |
| Here, the value stored on the stack copied to the object stored on the heap memory. |
Here, the object stored on the heap memory copied to the value stored on the stack . |
Example:
// C# program to illustrate Boxing
using System;
public class GFG {
static public void Main()
{
int val = 2019;
// Boxing
object o = val;
// Change the value of val
val = 2000;
Console.WriteLine("Value type of val is {0}", val);
Console.WriteLine("Object type of val is {0}", o);
}
}
Output:
Value type of val is 2000
Object type of val is 2019
|
Example:
// C# program to illustrate Unboxing
using System;
public class GFG {
static public void Main()
{
int val = 2019;
// Boxing
object o = val;
// Unboxing
int x = (int)o;
Console.WriteLine("Value of o is {0}", o);
Console.WriteLine("Value of x is {0}", x);
}
}
Output:
Value of o is 2019
Value of x is 2019
|