Add时出错 错误信息: Index was outside the bounds of the array. 详细信息: at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add) at ****.GetEnumDescription(Enum value) at ****.Page_Load(Object sender, EventArgs e) at System.Web.Ut…
懒汉模式和饿汉模式: public class Demo { //private static Single single = new Single();//饿汉模式 private static Single single2 = null;//饿汉模式 public Demo() { if (single2 == null) {//1 single2 = new Single();//2 } } } 在多线程环境下,代码1和代码2之间,这里会有线程安全问题,线程A和线程B同时到代码1和代码2之…
一.饿汉式 缺点:不能懒加载 // 不能懒加载 public class SingletonObject1 { private static final SingletonObject1 instance = new SingletonObject1(); private SingletonObject1(){ } public static SingletonObject1 getInstance(){ return instance; } } 二.懒汉式(线程不安全) public clas…
