class Program
  {
    static void Main(string[] args)
    {
      SizeClass sizeClass = new SizeClass(){Width = 10, Length = 10};
      Console.WriteLine("赋值前：width={0},length={1}", sizeClass.Width, sizeClass.Length);

      var copyOfSizeClass = sizeClass;
      copyOfSizeClass.Length = 5;
      copyOfSizeClass.Width = 5;
      Console.WriteLine("赋值后：width={0},length={1}",sizeClass.Width, sizeClass.Length);
      Console.ReadKey();
    }
  }

  public class SizeClass
  {
    public int Width { get; set; }
    public int Length { get; set; }
  }

  public struct SizeStruct
  {
    public int Width { get; set; }
    public int Length { get; set; }
  }

class Program
  {
    static void Main(string[] args)
    {
      SizeStruct sizeStruct = new SizeStruct(){Length = 10, Width = 10};
      Console.WriteLine("赋值前：width={0},length={1}", sizeStruct.Width, sizeStruct.Length);

      var copyOfSizeStruct = sizeStruct;
      copyOfSizeStruct.Length = 5;
      copyOfSizeStruct.Width = 5;
      Console.WriteLine("赋值后：width={0},length={1}", sizeStruct.Width, sizeStruct.Length);
      Console.ReadKey();
    }
  }

class Program
  {
    static void Main(string[] args)
    {
      List<string> temp = new List<string>(){"my","god"};
      temp.ForEach(t => Console.Write(t + " "));
      Console.ReadKey();
    }

    public static void ChangeReferenceType(List<string> list)
    {
      list = new List<string>(){"hello", "world"};
    }
  }

class Program
  {
    static void Main(string[] args)
    {
      List<string> temp = new List<string>(){"my","god"};      
      ChangeReferenceType(temp);
      temp.ForEach(t => Console.Write(t + " "));
      Console.ReadKey();
    }

    public static void ChangeReferenceType(List<string> list)
    {
      list.Clear();
      list.Add("hello");
      list.Add("world");
    }
  }

class Program
  {
    static void Main(string[] args)
    {
      Size s = new Size(){Length = 10, Width = 10};
      ChangeStructType(s);
      Console.Write("Length={0},Width={1}", s.Length,s.Width);
      Console.ReadKey();
    }

    public static void ChangeStructType(Size size)
    {
      size.Length = 0;
      size.Width = 0;
    }
  }

  public struct Size
  {
    public int Length { get; set; }
    public int Width { get; set; }
  }

class Program
  {
    static void Main(string[] args)
    {
      Room r = new Room()
      {
        TableSize = new Size(){Length = 100, Width = 80},
        TvSize = new Size(){Length = 10, Width = 8}
      };

      r.TableSize.Length = 0;
      
      Console.WriteLine("table目前的尺寸是：length={0},width={1}", r.TableSize.Length, r.TableSize.Width);
      Console.ReadKey();
    }
  }

  public struct Size
  {
    public int Length { get; set; }
    public int Width { get; set; }
  }

  public struct Room
  {
    public Size TableSize { get; set; }
    public Size TvSize { get; set; }
  }

r.TableSize.Length = 0;

r.TableSize = new Size(){Length = 0, Width = 0};

class Program
  {
    static void Main(string[] args)
    {
      var oneSize = new Size() {Length = 10, Width = 10};
      var twoSize = oneSize;

      oneSize.Changed += (s, e) => Console.Write("Size发生了改变~~");
      oneSize.Length = 0;
      Console.ReadKey();
    }
  }

  public class Size
  {
    private int _length;
    private int _width;

    public event System.EventHandler Changed;

    public int Length
    {
      get { return _length; }
      set
      {
        _length = value;
        OnChanged();
      }
    }

    public int Width
    {
      get { return _width; }
      set { _width = value; OnChanged(); }
    }

    private void OnChanged()
    {
      if (Changed != null)
      {
        Changed(this, new EventArgs());
      }
    }
  }

  public struct Room
  {
    public Size TableSize { get; set; }
    public Size TvSize { get; set; }
  }

class Program
  {
    static void Main(string[] args)
    {
      var size = new SizeStruct();
      Console.WriteLine("length={0},width={1}", size.Length, size.Width);
      Console.ReadKey();
    }
  }

  public struct SizeStruct
  {
    public int Length { get; set; }
    public int Width { get; set; }
  }

class Program
  {
    static void Main(string[] args)
    {
      var size = new SizeClass();
      Console.WriteLine("length={0},width={1}", size.Length, size.Width);
      Console.ReadKey();
    }
  }

  public class SizeClass
  {
    public int Length { get; set; }
    public int Width { get; set; }

    public SizeClass(int length, int width)
    {
      Length = length;
      Width = Width;
    }
  }

public struct SizeStruct
  {
    public int _length = 10;
  }

public struct SizeStruct
  {
    public int _length;

    public SizeStruct()
    {
      _length = 10;
    }
  }