单件模式
- 整个系统中对象是唯一的
- 也可以有固定数目个
如：对象池、portal中的配置对象 当前httpcontext appdomain
应用实列(一)
using System;
namespace CSDesingPattern
{
class Singleton
{
private static Singleton mInstance;
private int x = 0;
private Singleton() { }
public static Singleton GetObject()
{
if (mInstance == null)
mInstance = new Singleton();
return mInstance;
}
{
x = newVal;
}
{
return x;
}
{
Singleton s1 = Singleton.GetObject();
Singleton s2 = Singleton.GetObject();
Console.WriteLine("将Singleton对象中的X设置为10");
s1.SetX(10);
val = s2.GetX();
Console.WriteLine("使用第二个Singleton变量读取X的值 x={0}", val);
}
}
}
namespace CSDesingPattern
{
class Singleton
{
private static Singleton mInstance;
private int x = 0;
//私有构造函数
private Singleton() { }
//实现单件实例
public static Singleton GetObject()
{
if (mInstance == null)
mInstance = new Singleton();
return mInstance;
}
public void SetX(int newVal)
{
x = newVal;
}
public int GetX()
{
return x;
}
static void Main(string[] args)
{
int val;
Singleton s1 = Singleton.GetObject();
Singleton s2 = Singleton.GetObject();
Console.WriteLine("将Singleton对象中的X设置为10");
s1.SetX(10);
val = s2.GetX();
Console.WriteLine("使用第二个Singleton变量读取X的值 x={0}", val);
}
}
}