Decoration Mode Instance

User requirements:

Design ideas:

1.UML Figure

2. Use the decorative mode to dynamically add some additional functionality to an object, providing a more resilient alternative than inheritance for extended functionality.

Specific code implementation:

1. Abstract Components

Moilephone class

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;namespaceylx{ Public Abstract classMobilephone { Public Abstract voidSendMessage ();  Public Abstract voidCall ();  Public Abstract stringShow (); }} 　　 

2. Specific components

Apple class

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;namespaceylx{ Public classApple:mobilephone { Public Override voidSendMessage () {Console.WriteLine ("Apple features: Texting"); }         Public Override voidCall () {Console.WriteLine ("Apple features: Call"); }         Public Override stringShow () {stringstr ="Apple features: send SMS \ n"+"Apple features: Call \ n"; returnstr; }    }}

mi class

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;namespaceylx{ Public classMi:mobilephone { Public Override voidSendMessage () {Console.WriteLine ("mi function: Send SMS"); }         Public Override voidCall () {Console.WriteLine ("mi function: Call"); }         Public Override stringShow () {stringstr ="mi function: send SMS \ n"+"mi function: Call \ n"; returnstr; }    }}

3. Abstract Decoration class

function Class

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;namespaceylx{ Public Abstract classFunction:mobilephone {PrivateMobilephone Mobilephone;  Public voiddecorate (mobilephone phone) {mobilephone=phone; }         Public Override voidSendMessage () {mobilephone.        SendMessage (); }         Public Override voidCall () {mobilephone.        Call (); }         Public Override stringShow () {stringStr=Mobilephone.            Show (); returnstr; }    }}

4. Specific decoration category

Bluetooth class

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;namespaceylx{ Public classbluetooth:function { Public voidconnection () {Console.WriteLine ("Bluetooth module: Connection function"); }         Public Override stringShow () {stringStr=Base. Show () +"Bluetooth module: connection function \ n"; returnstr; }    }}

GPS class

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;namespaceylx{ Public classgps:function { Public stringLocation ;  Public Override stringShow () { location="This is the school of Science and Technology of Ningbo University \ n"; stringstr =Base. Show () +"GPS module Positioning function:"+Location ; returnstr; }    }}

Cemera class

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;namespaceylx{ Public classcemera:function { Public Override voidCall () {Console.WriteLine ("Call feature Upgrade: Video Call"); }         Public Override stringShow () {stringstr =Base. Show () +"Call feature upgrade: Video Call \ n"; returnstr; }    }}

Client

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;namespaceylx{classProgram {Static voidMain (string[] args) {Mobilephone Apple=NewApple (); Mobilephone mi=NewMi (); Bluetooth bluetooth=NewBluetooth (); Bluetooth.                      Decorate (apple); GPS GPS=NewGPS (); Gps.                       Decorate (Bluetooth); Cemera Cemera=NewCemera (); Cemera.            Decorate (GPS); Console.WriteLine (Cemera.                 Show ()); Bluetooth bluetooth1=NewBluetooth (); Bluetooth1.                       Decorate (MI); Cemera Cemera1=NewCemera (); Cemera1.            Decorate (bluetooth1); Console.WriteLine (Cemera1.            Show ());        Console.read (); }    }}

Operation Result:

Experience and sentiment:

Advantages:

Decoration patterns can provide more flexibility than inheritance, extending the functionality of an object in a dynamic manner, and creating a combination of many different behaviors by using different decorative classes and the arrangement combinations of these decorations.

the concrete structure class and the concrete adornment class can change independently.

Disadvantages:     

When you use adornment mode, you produce many small objects that are more error-prone than inheritance.

Applicable scenarios:

It is useful for adding responsibilities to a single object in a dynamic, transparent manner without affecting other objects. These functions can also be dynamically revoked when it is necessary to dynamically add functionality to an object.

Decoration Mode Instance