Design patterns, principles

1. Object clone (copy prototype model)

 

 

 

• scenes to be used:
  • You do not want to hold the referenced object type is modified (Our Common Object a = new Object (); Object b; b = a; copy of this form of the code is a reference to that object's address in memory, a and b object is still pointing to the same object)
  • Guarantee reference type parameter is not modified by other methods
  • Values ​​clones can be used as an argument
  • An object database needs to be created after a costly operation, we can cache the object and returns a clone of it directly at the next call, when you need to update the database to reduce calls to the database
• Use advantages:
  • Create duplicate objects, while ensuring performance (performance improvement)
  • Constraint constructor escape;
• Cloning Methods:
  • Shallow copy: Achieved interfaces ICloneable interface call MemberwiseClone () method Clone () method.
  • Deep copy: the object is serialized as data, the data again deserialize new object
• Case:
  • Nop.Core.Domain.Common.Address
  • Nop.Web.Models.Polls.PollModel
  • Nop.Web.Models.News.HomepageNewsItemsModel
• related articles:
  • https://blog.csdn.net/aHardDreamer/article/details/89601832
  • https://www.cnblogs.com/Qian123/p/5710533.html