Asp.Net 设计模式 之 单例模式

 1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Text; 5 using System.Threading.Tasks; 6 ?7 namespace SingleCaseModel00 8 { 9 ????/// <summary>10 ????/// 1.创建这么一个类11 ????/// </summary>12 ????class SingleCase13 ????{14 ????????//2.构建类类型静态变量15 ????????//此处类类型：如果当前类为SingleCase，则次静态变量类型也要为SingleCase类型，16 ????????//即在此处定义的静态变量的类型要和这个当前类的类型相同17 ????????//定义单例实例变量时，尽量都用instance（实例）来指代，方便阅读18 ????????//静态变量在内存中只有一个，只占一份儿19 ????????public static SingleCase instance = null;20 ????????//10.定义一个字段，用来进行测试21 ????????public string name;22 ????????//3.定义返回值类为单例类型的静态方法23 ????????public static SingleCase getInstance(string n)24 ????????{25 ????????????//4.判断静态变量instance是否为空26 ????????????if (instance == null)27 ????????????{28 ????????????????//5.如果为空，就创建实例29 ????????????????instance = new SingleCase();30 ????????????????//6.给单例类中的字段进行赋值31 ????????????????instance.name = n;32 ????????????}33 ????????????//7.返回此变量34 ????????????return instance;35 ????????}36 ????????//8.如果这个类中还有其他的字段，那么直接在下面写出来即可37 ????????//如下:38 ????????//public string Name;39 ????????//public int Age;40 ????}41 ????class Program42 ????{43 ????????static void Main(string[] args)44 ????????{45 ????????????//9.调用上述单例类中方法，测试单例类46 ????????????SingleCase s1 = SingleCase.getInstance("我是第一次传过来的参数");47 ????????????SingleCase s2 = SingleCase.getInstance("我是第二次传过来的参数");48 ????????????Console.WriteLine(s1.name);49 ????????????Console.WriteLine(s2.name);50 ????????????Console.ReadKey(); 51 ????????}52 ????}53 }