单例模式实现Demo

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;


namespace SearchScore.Factory
{
    public class SingleInterface
    {
        /// <summary>
        /// 创建一个内部访问的单例
        /// </summary>
        private static volatile ExamInterface.ExamInterface singleInterface = null;

        /// <summary>
        /// 创建一个多线程锁
        /// </summary>
        private static object lockObj = new object();

        /// <summary>
        /// 私有化一个单例构造函数
        /// </summary>
        private SingleInterface() {}

        /// <summary>
        /// 提供外部访问的一个实例化属性
        /// </summary>
        public static ExamInterface.ExamInterface Interface
        {
            get
            {
                if (singleInterface == null)
                {
                    //锁住,避免多线程重复创建
                    lock (lockObj)
                    {
                        if (singleInterface == null)
                        {
                            singleInterface = new ExamInterface.ExamInterface();
                        }
                    }
                }
                return singleInterface;
            }
        }
    }
}