Harshad, PHP Pandit - Apache, MySQL, PHP, Ajax, Soap, eBay & Amazon api, PHP Java Bridge

eBay Trrading Service Api's Calls

2009-06-04T07:39:00.001-07:00

Overview of Calls

AddDispute
AddDisputeResponse
AddFixedPriceItem
AddItem
AddItems
AddLiveAuctionItem
AddMemberMessageAAQToPartner
AddMemberMessageRTQ
AddMemberMessagesAAQToBidder
AddOrder
AddSecondChanceItem
AddToItemDescription
AddToWatchList
AddTransactionConfirmationItem
ApproveLiveAuctionBidders
CompleteSale
ConfirmIdentity
DeleteMyMessages
EndFixedPriceItem
EndItem
EndItems
FetchToken
GetAccount
GetAdFormatLeads
GetAllBidders
GetApiAccessRules
GetAttributesCS
GetAttributesXSL
GetBestOffers
GetBidderList
GetCategories
GetCategory2CS
GetCategory2FinanceOffer
GetCategoryFeatures
GetCategoryListings
GetCategoryMappings
GetCategorySpecifics
GetChallengeToken
GetCharities
GetClientAlertsAuthToken
GetContextualKeywords
GetCrossPromotions
GetDescriptionTemplates
GetDispute
GeteBayDetails
GeteBayOfficialTime
GetFeedback
GetFinanceOffers
GetItem
GetItemRecommendations
GetItemsAwaitingFeedback
GetItemShipping
GetItemTransactions
GetLiveAuctionBidders
GetLiveAuctionCatalogDetails
GetMemberMessages
GetMessagePreferences
GetMyeBayBuying
GetMyeBayReminders
GetMyeBaySelling
GetMyMessages
GetNotificationPreferences
GetNotificationsUsage
GetOrders
GetOrderTransactions
GetPictureManagerDetails
GetPictureManagerOptions
GetPopularKeywords
GetProductFamilyMembers
GetProductFinder
GetProductFinderXSL
GetProducts
GetProductSearchPage
GetProductSearchResults
GetProductSellingPages
GetPromotionalSaleDetails
GetPromotionRules
GetSearchResults
GetSellerDashboard
GetSellerEvents
GetSellerList
GetSellerPayments
GetSellerTransactions
GetSessionID
GetShippingDiscountProfiles
GetStore
GetStoreCategoryUpdateStatus
GetStoreCustomPage
GetStoreOptions
GetStorePreferences
GetSuggestedCategories
GetTaxTable
GetTokenStatus
GetUser
GetUserContactDetails
GetUserDisputes
GetUserPreferences
GetVeROReasonCodeDetails
GetVeROReportStatus
GetWantItNowPost
GetWantItNowSearchResults
IssueRefund
LeaveFeedback
PlaceOffer
RelistFixedPriceItem
RelistItem
RemoveFromWatchList
RespondToBestOffer
RespondToFeedback
RespondToWantItNowPost
ReviseCheckoutStatus
ReviseFixedPriceItem
ReviseItem
ReviseLiveAuctionItem
ReviseMyMessages
ReviseMyMessagesFolders
RevokeToken
SellerReverseDispute
SendInvoice
SetMessagePreferences
SetNotificationPreferences
SetPictureManagerDetails
SetPromotionalSale
SetPromotionalSaleListings
SetShippingDiscountProfiles
SetStore
SetStoreCategories
SetStoreCustomPage
SetStorePreferences
SetTaxTable
SetUserNotes
SetUserPreferences
UploadSiteHostedPictures
ValidateChallengeInput
ValidateTestUserRegistration
VerifyAddFixedPriceItem
VerifyAddItem
VerifyAddSecondChanceItem
VeROReportItems

eBay Trading Web Services - overview

2009-06-04T07:22:00.000-07:00

eBay trading Web Service provides programmatic access to the eBay marketplace. It enables third-party applications to build custom applications, tools, and services that leverage the eBay marketplace in new ways.

Trading API gives you an ability to add item, manage item, shipment and generate invoice ability and much more.

Typical eBay-enabled applications include item sales management (which could include integration with database inventory systems), item search utilities, user account management systems, systems that embed partner item listings in their Web pages, and applications that assist buyers in managing the listings they're interested in.

The power of eBay Web Services lies in making these applications possible independently of the eBay user interface. That is, your application doesn't need to change every time the eBay user interface changes, and it doesn't need to present data in the same way eBay does. Your eBay-enabled application can present data in custom ways that best meet your users' needs.

you can use this api via REST or SOAP .

The SOAP API is built on open standards like SOAP and WSDL. These standards are supported by a wide-range of development tools on a variety of platforms.

Both the XML API and the SOAP API share the same schema, so the basic format of the input and output data is the same no matter which API you use. Regardless of whether you are using the SOAP API or the XML API, you are accessing the same eBay functionality and data. Thus, you can choose to use one or the other or both—whichever approach is best for you.

Note: some information is pull from eBay Trading API documentation

OOPS Questioners

2008-01-09T03:09:00.001-08:00

1. What is a class?

Ans: A class is a set of methods and data items combined in a single entity. It provides some service or does some work and serves as a functionality package.

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2. What is an object?

Ans: An object is an instance of a class. A class is essentially a data type, and an object is a variable of that data type.

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3. Define what an attribute or property of an object is.

Ans: An attribute or property is a piece of data in a class. It has a value at any given time and may be readable, writable, or both.

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4. Define what an object behavior is.

Ans: Object behavior defines how an object works under certain operations.

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5. Describe the methods and attributes of a Card class to represent a card used in card games.

Ans: Attibutes: Suit, Value, FaceUp

Methods: GetSuit, SetSuit, GetValue, SetValue, IsFaceUp, Flip

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6.Define inheritance.

Ans: Inheritance means that a class is based upon the methods and attributes of an existing class.

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7.Describe the benefits of inheritance.

Ans: Code reuse

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8.Which of these is a base class: Vehicle or Minivan?

Ans: Vehicle, because a minivan "is a” vehicle—the minivan is derived from vehicle.

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9.Which is an example of inheritance: an Engine class and a Diesel class, or an Engine class and a Car class?

Ans:Engine and Diesel, because Diesel "is a” type of engine. A Car "has a(n)” engine, which describes containment, not inheritance.

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10.What is a business object?

Ans: A business object is a class used by a business system or application, such as an order form.

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11.What is a characteristic?

Ans: A characteristic is an attribute or method that distinguishes two classes.

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12.What is a class definition?

Ans: A class definition defines attributes and methods that are members of the class.

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13.What is an argument list?

Ans: An argument list is a list of data items passed to a method or function for it to do its job.

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14.What is a return value?

Ans: A return value is a value that a method returns as its output or result. Return values are optional.

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15.If Engine were a class in Java, how would you define an instance of it?

Ans: Engine anEngine = new Engine();

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16.If Engine were a class in C++, how would you define an instance of it?

Ans: Engine anEngine;

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17.What is a constructor?

Ans: A constructor is a special method that initializes the attributes of a class.

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18.What is a destructor?

Ans:A destructor is a special method that releases any resources (such as memory) from an object instance. Java does not implement "true” destructors, while C++ does because Java performs garbage collection while C++ doesn’t (and garbage collection is not guaranteed to run before the program terminates).

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19.What is garbage collection?

Ans: Garbage collection is the ability of a language to automatically remove objects created in memory when the last reference or use of the object goes out of scope or is no longer needed.

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20.How do you access members of an object?

Ans: In Java, C++, and C#, you use the dot (.) operator. C++ also uses the arrow (->) operator if you have a pointer to an object.

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21.Define encapsulation.

Ans: Encapsulation is the grouping of concepts or behaviors into a class. It defines how the class behaves, without offering details as to how it implements that behavior.

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22.Define polymorphism.

Ans: Polymorphism means that something has many shapes and that something is a method of an object-oriented programming language. In programming terms, a thing is the name of a method and a shape is the behavior performed by a method. Polymorphism means that one or more methods with the same name exist for many behaviors.

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23.Define overloading.

Ans: Overloading is another one of those terms you hear used in conjunction with polymorphism. Overloading means that two or more methods are defined using the same name, but with different argument list.

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24.Define binding.

Ans: Binding is the association of a method definition (or function body) with a call to a method, and occurs either at compile time or at runtime. Compile-time or Early binding is used for normal method calls. No time is lost when the program runs because binding is completed when the executable program is created. Runtime or Late binding is implemented using a virtual function, which uses a base reference to point to the type of object that contains the correct method definition.

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25.Define runtime polymorphism.

Ans: Run-time polymorphism uses virtual functions to create a standard interface and to call the underlying functions. Those function definitions are bound to function calls during run time.

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26.What is a virtual function?

Ans: A virtual function is used to trick the computer into thinking a function is defined, but the function doesn’t have to be defined at that moment. Instead, the virtual function can be a placeholder for the real function that is defined in a program. Virtual functions help support run-time polymorphism.

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27.How would you define a virtual method in C++?

Ans: Use the keyword virtual in the declaration of the method, such as Foo:

class Boo {public:virtual void Foo();};

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28.How would you define a virtual method in Java and C#?

Ans: Methods are virtual in Java and C# by default. To create a virtual method without any body in these languages, use the abstract keyword in the declaration of the method.

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29.Define method overloading.

Ans: Method Overloading is a technique to implement polymorphism by defining two or more methods with the same name but different argument list.

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30.Compare Public, Protected, and Private members of a class.

Ans: Public members are seen by all methods, even ones outside the class. Protected members are seen only to that class and ones derived from it. Private members are seen only by that class, and nothing else.

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31.Define simple inheritance.

Ans: Simple inheritance occurs when there is one parent-child relationship—that is, one child inherits from one parent.

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32.Define multiple inheritance.

Ans: Multiple inheritance is where there is a multiple parent-child relationship. The child inherits from more than one parent. Java and C# do not support multiple inheritance, but C++ does.

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33.What is the "Diamond Problem” of multiple inheritance?

Ans: It describes a situation where a single base class (such as Person) contains a data member such as Name, and then two classes are derived from it such as Student and Instructor. Now that Student and Instructor contain a Name member, if we were to create a new class derived from both (such as a TeachingAssistant class), then the object could have two names for what is really one person.

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34.Define level inheritance.

Ans: Level inheritance happens when a child inherits from a parent and then becomes a parent itself to a child.

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35.What is the maximum number of levels for level inheritance?

Ans: There is no practical limit—if you find a compiler that can’t handle 1,000 levels of inheritance, the real problem is that you have a poor design because there are too many levels of inheritance. A rule of thumb is to try and limit things to three levels.

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36.What are the terms typically used to refer to the parent and child classes in C++ and Java?

Ans: C++ typically uses the terms base class and derived class, while Java typically uses super class and subclass.

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37.Define abstraction.

Ans: Abstraction is a way a programmer of a super class forces a programmer of a subclass to define a behavior.

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38.What is the difference between functionality and function?

Ans: Programmers distinguish a behavior from instructions used to perform the behavior using the term’s functionality and function.

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39.What is an abstract method?

Ans: An abstract method does not provide a method body. A class with an abstract method requires derived classes to implement the method body. A class with an abstract method is called an abstract class. Abstract methods are called "pure virtual” methods in C++.

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40.Define an abstract class.

Ans: An abstract class is one that has one or more abstract methods. Because of this, you cannot instantiate an object of this type. You must create a derived class that provides the method bodies for the abstract methods, and then you can instantiate the derived class.

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41.What is data decomposition?

Ans: Object-oriented programmers decompose each attribute into data and then use data in the corresponding class definition to describe the object. Decomposition is the technique that reduces an attribute into its data components.

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42.What is an iconic description?

Ans: An iconic description is a graphic picture of the process. Textual description describes the process in words.

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43.Define pseudo code.

Ans: Pseudo code is a combination of English words and programming language syntax that describe in words how a process works. The result is not entirely English, nor a syntactically correct program. It’s used to enforce understanding and requirements without actually writing a program.

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44.What is an entity?

Ans: An entity refers to an individual item, and may be a single piece of data or an object.

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45.What is an entity relationship?

Ans: Entity relationship (or functional relationship) describes how objects are related or interact with one another.

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46.What is a many-to-many relationship?

Ans: It defines a relationship between two different types (such as Student and Course) where any single first type (Student) can be related to 1 or more of the second type (Course), and vice versa. For example, one student may be registered in many courses, and a course may have many students.

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47.Define a leveling diagram.

Ans: A leveling diagram depicts an application in layers where the top level has the least amount of detail and is the easiest to understand. Subsequent levels have more detail and are usually the hardest to understand.

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48.What is a class diagram?

Ans: A class diagram is an illustration that describes a class, its attributes, and its behaviors.

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49.What is an internal model?

Ans: The internal model describes how an application works behind the scenes.

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50.What is an external model?

Ans: The external model describes how a person interacts with the application.

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51.What is the "is a" test?

Ans: The "is a” test asks the question is object A a type of object B. If so, then object A can inherit object B. For example, a Minivan is a type of Vehicle, so Minivan can be derived from Vehicle.

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52.What is the "has a” test?

Ans: The "has a” test asks the question does object A have an object B. If so, then object A would have a data member of type Object B. For example, a Vehicle has an Engine, so a Vehicle object would have an Engine object as a data member.

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53.Define collaboration.

Ans: Collaboration occurs when two or more things work together or cooperate with each other in order to achieve a common goal. In programming, it means that one class might have methods that call methods from another class.

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54.What is UML?

Ans: UML stands for Unified Modeling Language, and is a set of diagramming and text standard to help define a process and classes involved in the process.

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55.What is a sequence diagram?

Ans: A Sequence diagram is a diagram that shows the typical sequence of events for a process.

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56.What is a collaboration diagram?

Ans: Collaboration diagrams are used to display basic interaction between classes.

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57.What is a message?

Ans: When discussing collaboration, we typically say that a class collaborates with another via a Message. Technically, a message is a function call, so if we say that class A sends a message to class B, we are saying that class A is calling a method in a class B object.

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58.What is association?

Ans: Association means that the two classes need to know how to interact with one another, and is part of the description of collaboration.

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59.What is self-collaboration?

Ans: Self-collaboration is when a class invokes its own methods.

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60.What is a Class Responsibility Collaborator diagram?

Ans: The Class Responsibility Collaborator (CRC) diagram is intended to be an all-inclusive list of how a single class is to be designed. A CRC diagram lists the class name at the top, and then two columns below for responsibilities and collaborators.

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61.What is an actor?

Ans: An actor is a person, organization, or anything that might interact with a system. Actors don’t need to be persons. If a system needs to output a file in a certain format for a government agency, then that agency might be considered an actor as well.

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62.What is an SME?

Ans: An SME (Subject Matter Expert) is a person who has intimate knowledge about the work or process for which you are developing a system. They don’t need to have any computer experience.

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63.What is an Essential Use Case?

Ans: An Essential Use Case is a nontechnical view of how your system will work with its users.

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64.What is a System Case?

Ans: A System Use Case defines the technical view of how your system will work.

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65.What are business rules?

Ans: Business Rules are the rules and laws that govern how a business operates. An SME is typically the most accurate source of business rules.

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66.What is a User Interface diagram?

Ans: User Interface Diagrams are prototypes or designs for a programs user interface. It may contain forms and controls, as well as menu items.

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67.What is a User Interface-Flow diagram?

Ans: User Interface-Flow diagrams let you define the flow of the program in terms of the user interface, such as the steps a user must take to perform some process.

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68.What is a Change Case?

Ans: A Change case represents possible or definite changes to a system. The goal of the change case is to design a flexible system and anticipate possible or definite changes so that the system can be designed to be easily adaptable.

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69.What is an interface?

Ans: An interface represents a set of standard methods to provide some behavior or feature to a class. For a class to have some certain behavior, it declares that it will implement the interface that defines the behavior.

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70.Describe some of the basic units of project management.

Ans: Client—Entity for which the work is being done.

Project—The definition of the project and the group for the remaining items. Clients can have multiple projects.

Work Request—Identifies a request, feature, change, or bug report. Projects are made up of requests and features initially, and then as time goes on features, changes, and bug reports are added.

Task—The work performed by the entity developing the project. Tasks are the work performed to complete a Work Request.

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71.Describe three common errors when using abstraction.

Ans: Failure of a programmer to define an abstract method in a subclass, an attempt by the programmer to call the super class’s abstract method, and an attempt to declare an instance of the abstract super class in the program.

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72.What is a framework?

Ans: A framework is a set of classes or class library that has been designed to work well together and that follows a certain paradigm.

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73.Describe three basic categories of reuse.

Ans: Objects that are very reusable across different applications (like a string class or stream hierarchy), objects that are reusable within a particular set of programs (like a student class and hierarchy for academic institution programs), and objects that simply will never be reused again anywhere.

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74.How are approaches to OO programming analogous to nouns and verbs?

Ans: Objects are thought of as nouns (person, place, or thing). Tasks are thought of as verbs because they describe action within an application.

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75.How can a hierarchy be morphed?

Ans: A hierarchy is morphed when a member function has many versions of a behavior requiring many overloaded functions.

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76.When might you use multiple inheritance?

Ans: Multiple inheritance should be used whenever a child needs to inherit attributes and behaviors from parents that are not related to each other.

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77.What is early binding?

Ans: Early binding is the binding of a method call to a method definition and is performed at compile time if all the information is available at compile time.

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78.What is late binding?

Ans: Late binding is the binding of a method call to a method definition and is performed at run time. It implicitly makes use of base class pointers or references to derived objects, and methods must be virtual.

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79.Do UML sequence diagrams show flow control?

Ans: No. Unlike flow charts, Sequence diagrams do not show flow control; they show sequence.

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80.What is a finalize method in Java?

Ans: It represents the pseudo-destructor for a class. If garbage is collected, the finalize method is called, but there is no guarantee when or even if this will occur.

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81.What is the difference between static and non-static class members?

Ans: Nonstatic data members occur in each instance of the class and nonstatic methods can work with them as well as static methods. Static data members occur only once no matter how many instances of a class and static methods can only work directly with static data members. You do not need to declare an instance of a class to use its static methods or properties.

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82.What is the Java syntax to declare class Derived from class Base?

Ans: public class Derived extends Base { ...

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83.What is the C++ syntax to declare class Derived from class Base?

Ans: class Derived : public Base { ... // public may also be private or protected.

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84.What is the C# syntax to declare class Derived from class Base?

Ans: class Derived : Base { ...

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85.What does the final keyword in Java mean when applied to a class?

Ans: It means that no class can be derived from it.

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86.Is Java a compiled or interpreted language?

Ans: It is compiled into bytecode, and then the Java Virtual Machine interprets the byte code.

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87.Is C++ a compiled or interpreted language?

Ans: It is compiled into native machine code.

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88.Is C# a compiled or interpreted language?

Ans: It is compiled into byte code, and then the CLR recompiles it into native machine code.

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89.Which language supports multiple inheritance: Java, C++, or C#?

Ans: C++

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90.Which language offers the best portability to other platforms: Java, C++, or C#?

Ans: Java, since its bytecode can be used without recompiling. C# and the CLR are designed for this ability, but only currently available on Windows Desktop and Windows Mobile operating systems.

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91.Describe one advantage and disadvantage of garbage collection.

Ans: Garbage collection releases the programming from the task of manually releasing memory. The disadvantage is that garbage collection systems are unpredictable as to when they release memory and may require manual coding to do so.

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92.Which language provides the easiest access directly to memory?

Ans: C++, which supports pointers directly to memory. C# includes some support for memory access and Java provides none.

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93.Which languages support interfaces syntactically: Java, C++, or C#?

Ans: Java and C#. C++ can mimic this behavior by defining an abstract class and using multiple inheritance.

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94.Which languages support templates or generics: Java, C++, or C#?

Ans: C++ and Java version 1.5

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95.What are the three editions of Java?

Ans: J2EE—Java Enterprise Edition for servers, J2SE—Java Standard Edition for desktops, and J2ME—Java Micro Edition for handheld devices.

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96.What is the JVM?

Ans: The JVM, or Java Virtual Machine, is the program that must be installed on a computer in order to interpret and execute the compiled byte code of a Java program.

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97.What is the CLR?

Ans: The CLR, or Common Language Runtime, is the program that must be installed on a computer in order to interpret and compile the bytecode generated by compiling a C# program.

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98.What has the smallest footprint, memory-wise: Java, C++, or C#?

Ans: C++, because it doesn’t require a JVM or CLR to be in memory while it runs.

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99.What was one of the first stored-program computer systems?

Ans: ENIAC, built in the mid-1940s

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100.Where did the term "bug” come from?

Ans: Grace Hopper coined the term when she found a moth stuck between some tubes, which was causing her program to act incorrectly.

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what is AJAX?

2006-06-05T22:48:00.000-07:00

AJAX is Asynchronous JavaScript and XML.

A scripting technique for silently loading new data / web page from the server. Although AJAX scripts commonly use the soon to be standardized XMLHttpRequest object, they could also use a hidden iframe or frame. An AJAX script is useless by itself. It also requires a DOM Scripting component to embed the received data in the document.

In another way we can say Ajax, shorthand for Asynchronous JavaScript and XML, is a Web development technique for creating interactive web applications. The intent is to make web pages feel more responsive by exchanging small amounts of data with the server behind the scenes, so that the entire web page does not have to be reloaded each time the user makes a change. This is meant to increase the web page's interactivity, speed, and usability. The first known use of the term in public was by Jesse James Garrett in his February 2005 article Ajax: A New Approach to Web Applications. At subsequent talks and seminars Garrett has made the point that Ajax is not an acronym.

History of AJAX

Although the term 'Ajax' was coined in 2005, most histories of the technologies that enable Ajax start a decade earlier with Microsoft's initiatives in developing Remote Scripting. However techniques for the asynchronous loading of content on an existing web page without requiring a full reload date back as far as the IFRAME element type (introduced in Internet Explorer 3 in 1996) and the LAYER element type (introduced in Netscape 4 in 1997, abandoned during early development of Mozilla). Both element types had a src attribute that could take any external URL, and by loading a page containing JavaScript that manipulated the parent page, Ajax-like effects could be attained.

Microsoft's Remote Scripting (or MSRS, introduced in 1998) acted as a more elegant replacement for these techniques, with data being pulled in by a Java applet with which the client side could communicate using JavaScript. This technique worked on both Internet Explorer version 4 and Netscape Navigator version 4 onwards. Microsoft took first advantage of these techniques in Outlook Web Access supplied with the Microsoft Exchange Server 2000 release.

The web development community, first collaborating via the microsoft.public.scripting.remote newsgroup and later through blog aggregation, subsequently developed a range of techniques for remote scripting in order to enable consistent results across different browsers. In 2002, a user-community modification to Microsoft Remote Scripting was made to replace the Java applet with XMLHttpRequest.

Remote Scripting Frameworks such as ARSCIF surfaced in 2003 not long before Microsoft introduced Callbacks in ASP.NET.

Since XMLHttpRequest is now implemented across the majority of browsers in use, alternative techniques are used infrequently. However, they are still used where wide compatibility, small implementation, or cross-site access are required.

Pros, cons, and criticism

Pros

Interactivity
Ajax applications are mainly executed on the user's machine, by manipulating the current page within their browser using document object model methods. Ajax can be used for a multitude of tasks such as updating or deleting records; expanding web forms; returning simple search queries; or editing category trees—all without the requirement to fetch a full page of HTML each time a change is made. Generally only small requests are required to be sent to the server, and relatively short responses are sent back. This permits the development of more interactive applications featuring more responsive user interfaces due to the use of DHTML techniques.

While the Ajax platform is more restricted than the Java platform, current Ajax applications effectively fill part of the one-time niche of Java applets: extending the browser with lightweight mini-applications.

Cons and criticism

Usability criticisms
One major complaint voiced against the use of Ajax in web applications is that it might easily break the expected behavior of the browser's back button. The different expectations between returning to a page which has been modified dynamically versus the return to a previous static page might be a subtle one. Users generally expect that clicking the back button in web applications will move to their last page loaded, and in Ajax applications this might not be the case. Developers have implemented various solutions to this problem, most of which revolve around creating or using invisible IFRAMEs to invoke changes that populate the history used by a browser's back button. Google Maps, for example, performs searches in an invisible IFRAME and then pulls results back into an element on the visible web page; it is possible to track user behaviour via callbacks which are called whenever the back button is pressed, restoring the application state that existed at the time.

A related issue is that dynamic web page updates make it difficult for a user to bookmark a particular state of the application. Solutions to this problem exist, many of which use the URL fragment identifier (the portion of a URL after the '#' [1] [2]) to keep track of, and allow users to return to, the application in a given state. This is possible because many browsers allow JavaScript to update the fragment identifier of the URL dynamically, so that Ajax applications can maintain it as the user changes the application's state. This solution also improves back-button support.

Response-time concerns
Network latency — or the interval between user request and server response — needs to be considered carefully during Ajax development. Without clear feedback to the user [3], smart preloading of data and proper handling of the XMLHttpRequest object, users might experience delay in the interface of the web application, something which users might not expect or understand [4]. The use of visual feedback to alert the user of background activity and/or preloading of content and data are often suggested solutions to these latency issues.

In general the potential impact of latency has not been "solved" by any of the open source Ajax toolkits and frameworks available today, such as the effect of latency variance over time.

JavaScript
While no browser plug-in is required for Ajax, it requires users to have JavaScript enabled in their browsers. This applies to all browsers that support Ajax except for Microsoft Internet Explorer 6 and below which additionally require ActiveX to be enabled, as the XMLHTTP object is implemented with ActiveX in this browser. Internet Explorer 7, however, will implement this interface as a native JavaScript object and hence does not need ActiveX to be enabled for Ajax to work.

As with DHTML applications, Ajax applications must be tested rigorously to deal with the quirks of different browsers and platforms. A number of programming libraries have become available as Ajax has matured that can help ease this task. Likewise, techniques have been developed to assist in designing applications which degrade gracefully and offer alternative functionality for users without JavaScript enabled.

Name issues
There have been some critics of the term Ajax, claiming that Adaptive Path (the consulting firm that coined the term [5]) or other proponents are using it as a marketing vehicle for previously-used techniques.

Accessibility
Using Ajax technologies in web applications provides many challenges for developers interested in adhering to WAI accessibility guidelines. In addition there are numerous development groups working on government projects which require strict adherence to Section 508 Compliance standards. Failure to comply with these standards can often lead to cancellation of contracts or lawsuits intended to ensure compliance.

Because of this, developers need to provide fallback options for users on other platforms or browsers, as most methods of Ajax implementation rely on features only present in desktop graphical browsers.

Web developers use Ajax in some instances to provide content only to specific portions of a web page, allowing data manipulation without incurring the cost of re-rendering the entire page in the web browser. Non-Ajax users would ideally continue to load and manipulate the whole page as a fallback, allowing the developers to preserve the experience of users in non-Ajax environments (including all relevant accessibility concerns) while giving those with capable browsers a much more responsive experience.

That all AJAX is. in this article some of the content is importent for new programmer

PHP installation on Windows

2006-04-19T00:57:00.000-07:00

Installation on Windows systems
This section applies to Windows 98/Me and Windows NT/2000/XP. PHP will not work on 16 bit platforms such as Windows 3.1 and sometimes we refer to the supported Windows platforms as Win32. Windows 95 is no longer supported as of PHP 4.3.0.

There are two main ways to install PHP for Windows: either manually or by using the InstallShield installer.

If you have Microsoft Visual Studio, you can also build PHP from the original source code.

Once you have PHP installed on your Windows system, you may also want to load various extensions for added functionality.

Windows InstallShield
The Windows PHP installer is available from the downloads page at http://www.php.net/downloads.php. This installs the CGI version of PHP and, for IIS, PWS, and Xitami, configures the web server as well.

Note: While the InstallShield installer is an easy way to make PHP work, it is restricted in many aspects, as automatic setup of extensions for example is not supported. The whole set of supported extensions is only available by downloading the zip binary distribution.

Install your selected HTTP server on your system and make sure that it works.

Run the executable installer and follow the instructions provided by the installation wizard. Two types of installation are supported - standard, which provides sensible defaults for all the settings it can, and advanced, which asks questions as it goes along.

The installation wizard gathers enough information to set up the php.ini file and configure the web server to use PHP. For IIS and also PWS on NT Workstation, a list of all the nodes on the server with script map settings is displayed, and you can choose those nodes to which you wish to add the PHP script mappings.

Once the installation has completed the installer will inform you if you need to restart your system, restart the server, or just start using PHP.