相关疑难解决方法(0)

public sealed class Singleton
{
    Singleton() {}

    public static Singleton Instance
    {
        get
        {
            return Nested.instance;
        }
    }

    class Nested
    {
        // Explicit static constructor to tell C# compiler
        // not to mark type as beforefieldinit
        static Nested() {}
        internal static readonly Singleton instance = new Singleton();
    }
}

我希望在我目前的C#应用​​程序中实现Jon Skeet的Singleton模式.

我对代码有两个疑问

1. 如何访问嵌套类中的外部类？我的意思是

   internal static readonly Singleton instance = new Singleton();
   

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   有什么叫封闭吗？

2. 我无法理解这个评论

   // Explicit static constructor to tell C# compiler
   // not to mark type as beforefieldinit …

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public class MySingletonClass
{
  public MySingletonClass()
  {
    _mySingletonObj = Instance();
  }

  public static MySingletonClass Instance()
  {
    if (_mySingletonObj  == null)
    {
      lock (typeof(lockObject))
      {
        if (_mySingletonObj  == null)
          _mySingletonObj  = new MySingletonClass();
      }
    }
    return _mySingletonObj ;
  }
}

MySingletonClass _myObj = new MySingletonClass();

这个作为公共建设者的单身人士......？

谢谢