tag:blogger.com,1999:blog-61099024283945912352024-09-09T11:25:32.387+05:30Vikas Goyalnoreply@blogger.comBlogger17125tag:blogger.com,1999:blog-6109902428394591235.post-48527269082811834482011-07-14T11:43:00.001+05:302011-07-14T11:43:29.876+05:30

  Programming with HTML5 and related technologies http://www.microsoft.com/showcase/en/in/details/4f39070b-c435-4de5-9f50-0d2852c1dfbe Visual Studio 2010 SP1 for Web Developers http://www.microsoft.com/showcase/en/in/details/90b79e80-eae9-47c8-a4f4-a2431e62178d ASP.NET MVC3 Development with Visual Studio 2010 http://www.microsoft.com/showcase/en/in/details/fd907f28-bcbd-4a00-871f-

Vikas Goyalnoreply@blogger.com2tag:blogger.com,1999:blog-6109902428394591235.post-49592121179760679842008-02-06T15:35:00.001+05:302008-02-06T15:35:04.467+05:30

Iterator Behavioral Pattern provides an access interface to an aggregate or collection object for clients. The iterator abstracts the clients from how the collection has been structured and also provides sequential navigation capabilities over collection. Consider the following class diagram : NodeCollection type holds objects of type Node and there are two Iterators provided for

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-55314062952091114532008-01-28T15:55:00.001+05:302008-01-28T15:55:21.552+05:30

Interpreter Behavioral Pattern as name suggests is used to interpret sentences in langauge provided represented in a particular form. The langauge should be representable in form of abstract syntax tree. Two types of nodes are used for expressions : Terminal Expressions & Non-Terminal Expressions. Let's take an example of a command line calculator which can take expressoins in form of a+b-c

Vikas Goyalnoreply@blogger.com2tag:blogger.com,1999:blog-6109902428394591235.post-12376904309147234122008-01-15T12:50:00.001+05:302008-01-15T12:50:18.218+05:30

Command Patterns helps encapculating/mapping a request to object called command. All commands are derived from base command which has mainly two methods Execute & UnExecute. The commands forwards the request data to Receiver for further processing. Either client can decide which Command and  Receiver to be invoked or it can be configuration based for loose coupling. One of the popular

Vikas Goyalnoreply@blogger.com1tag:blogger.com,1999:blog-6109902428394591235.post-78834730600164587632008-01-10T16:14:00.001+05:302008-01-10T16:14:15.537+05:30

ChainOfResponsibility Behavioral Pattern helps achieving loose coupling between request sender and receiver object. It helps in introducing a set of chained interceptor objects which can handle the request or pass it to next member in chain. The chaining can be pre-configured or can be done by client before invoking the chain. Consider the below class diagram: Based on the base exception

Vikas Goyalnoreply@blogger.com1tag:blogger.com,1999:blog-6109902428394591235.post-29242888181881983772007-11-06T11:02:00.001+05:302007-11-06T11:02:23.842+05:30

Flyweight Structural Pattern is used to manage large number of shared objects. They are maintained in a collection and same instances used whenever required. These objects have their own attributes/features but they can have a common feature also which can be externalized. Consider a scenario where a picture has to be drawn which consists of large numbers of polygons of different colors. All

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-39399103603761526782007-10-18T16:09:00.001+05:302007-10-18T16:09:43.493+05:30

'Facade Structural Pattern' is primarily used to unify and simply a set of interfaces of subsystems. This helps the client in using the interface with less effort. Consider the class diagram below : Above shows a typical scenario of a Bank where a new Customer approaches the Bank to open new account and also deposit some initial amount. The Core Banking subsystems provide two different

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-35764303366974132252007-10-15T15:52:00.001+05:302007-10-15T15:52:00.295+05:30

The primary use of 'Decorator Structural Pattern' is to add behaviors to object at runtime. It generally involves wrapping the original object with the decorator object which adds the new behaviors but keep the structure of original object intact. Multiple behaviors can be added out of given options based on decision criteria. Consider the class diagram below : There is a BookBase class

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-39497218294269232222007-10-09T10:08:00.001+05:302007-10-09T10:08:57.103+05:30

Composite Structural Pattern is applicable when you need to deal with whole-part kind of relationships or tree kind of structures. It helps client to deal with individual or composite objects in a uniform manner and thus abstracts the client from complexities of internal structure. Consider the following class diagram : In the above diagram Book is a simple type but LibrarySection is a

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-58562141783140854552007-10-05T10:54:00.001+05:302007-10-05T10:57:18.456+05:30

Bridge Structural Pattern decouples an abstraction from its implementation so that the two can vary independently. Multiple variants of abstraction can be created provided they implement the common interface. Similarly, multiple variants of implementations can be created provided they implement the common interface. Given the option of multiple abstraction variants and multiple implementation

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-45289669456665281212007-10-03T13:40:00.001+05:302007-10-03T15:25:19.138+05:30

Adapter pattern also called as Wrapper pattern lets client adapt a framework/service with different call definitions than what client has been designed for. Clients continue using the original definitions and adapter takes care of transformation. Consider the class diagram below : Client calls the ClientBase class which is client's default framework. Now Client is supposed to use

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-63013186610764856032007-09-28T10:10:00.001+05:302007-09-28T10:10:27.499+05:30

One of the most popular creational pattern. It is used to restrict the number of instances of a type to one and so all clients use the same instance. Consider the following class diagram : Client creates two variables of type Singleton, s1 and s2.  The client code looks like following : public class Client { Singleton s1,s2; public void Run() { // s1

Vikas Goyalnoreply@blogger.com1tag:blogger.com,1999:blog-6109902428394591235.post-85084674859043918482007-09-24T12:49:00.001+05:302007-09-24T15:51:37.881+05:30

Prototype Creational Pattern provides an interface which can be used by client to get access to already existing instance of a type which can be used as prototype by client to create new instance. Client can clone the existing object using deep or shallow copy and use it. It is used mainly when inherent cost of creating a new object is high. Consider the following class diagram : Above scenario

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-21693093851682180792007-09-24T10:16:00.001+05:302007-09-24T10:16:32.891+05:30

It provides an interface for creating an object but lets subclass decide which class to instantiates. So, it can also be called as virtual constructor. Consider the following class diagram : ShapeCreator class provides an factory method to create objects of BaseShape. Client always uses ShapeCreator and BaseShape type variables to work on instances of derives classes. The client looks like

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-65344018342338871582007-09-21T15:30:00.001+05:302007-09-21T15:30:09.758+05:30

Builder Creational Pattern separates the process of construction of a complex object from its actual representation. This means that the same process can create different representations of same object. Consider the following diagram : The main class here is ShapeCreator which is called Director and controls the process of construction of object.  // Director public class

Vikas Goyalnoreply@blogger.com0tag:blogger.com,1999:blog-6109902428394591235.post-26021840877845106592007-09-20T11:36:00.001+05:302007-09-20T11:36:39.862+05:30

Provides a single interface for creating families of related or dependent objects without using the concrete type name. Consider the following class diagram : In above diagram, CreateShapes acts as an single interface for creating various families of products. The diagram shows only Red shapes but it can be extended to create more color shapes. The client code will look like this : public

Vikas Goyalnoreply@blogger.com1tag:blogger.com,1999:blog-6109902428394591235.post-41011059904672179172007-09-19T14:32:00.001+05:302007-09-19T14:39:56.494+05:30

Over next few days, I will be discussing the implementation of GOF design patterns in CSharp. I wont be discussing the benefits of Design Patterns here ... you can read about them here : Design Patterns. In one line : "They bring best practice for solving common design problems to software development which helps in ensuring success of design and increase in productivity." Here is a quick

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