Introduction to C#

What is Structure in C#

Structure is a user-defined value type which encapsulates member data and member function.

A struct is a user-defined value type. It is declared in a very similar way to a class, except that it can't inherit from any class, nor can any class inherit from it (as mentioned\ previously, however, all value types do inherit from System.object), The following example shows a partial declaration for a 'Coordinate' struch.

What is enumeration in C#

An enumeration is a special set of numeric type string literals which considered as a constants.

An enumeration is a special kind of value type limited to a restricted and unchangeable set of numerical values. By default, these numerical values are integers, but they can also be longs, bytes, etc. (any numerical/value except char) as will be illustrated below.

 

Type of String in C#

A string is an empty space, a character, a word, or a group of words.

A string is an empty space, a character, a word, or a group of words that you want the compiler to consider "as is", that is, not to pay too much attention to what the string is made of, unless you explicitly ask it to. This means that, in the strict sense, you can put in a string anything you want.

Type of Array

An array is a group or collection of similar type of elements.

An array is a group or collection of similar values. An array contains a number of variables, which are accessed through computed indexes. The various value contained in an array are also called the elements of array. All elements of an array have to be of same type, and this type is called the element type of the array. The element of an array can be of any type including an array type.

What is Scope of Variable

In the body of a method, you can also declare variables that would be used internally. A variable declared in the body is referred to as a local variable. It cannot be accessed outside of the method it belongs to. After declaring a local variable, it is made available to the method and you can use it.

Type of Method in C#

The Function defined with in class is called method. It is a code designed to work on the member data of class.

Methods are operations associated with types. To provide a type with methods is to give it some useful functionality. Often this functionality is made generally available, so that it can be utilized by other types.

Multiple Main() Functions in C#

C# has a strong feature in which we can define more than one class with the Main method. Since Main is the entry point for the program execution, there are now more than one entry points. In fact, there should be only one entry point. Which will be resolved by specifying which Main is to be used to the compiler at the time of compilation as shown below:

Command Line Arguments

Command line arguments are parameters supplied to the Main method at the time of invoking it for execution. To understand the concepts see the example given below:

Program of Command line argument to accept name from the command line and writes to the console. (Sample.cs)

What is Namespace in C#

When many people work in creating the same program, it could be difficult to keep track of the names of various classes. If more than one programmer creates a class with the same name in the same program, there would be conflict and the program would not work. The solution to avoid this situation is to delimit sections of code with names.

Types of Statements in C#

Like C++ it contains three types of statements.

1. Simple Statements

2. Compound Statements

3. Control Statements

A Simple C# Program

Let's begin in the traditional way, by looking at the code of a Hello World program.

1. using System;

2. public class HelloWorld

3. {

4. public static void Main()

5. {

6. II This is a single line comment

7. /* This is a

8. multiple

9. line comment */

10. Console.WriteLine("Hello World! ");

11. }

12. }

Explain C# Data Type

C# is a type-safe language Variables· are declared as .being of a particular type; and each variable is constrained to hold only values of its declared type.

Variables can hold either value types or reference types, or they can be pointers. Here's a quick recap of the difference between value types and reference types.

C# KEYWORDS

C# uses a series of words, called keywords, for its internal use. This means that you must avoid naming your objects using one of these keywords.

Identifiers And Variables

Identifiers refer to the names of variables, functions arrays, classes, etc. created by programmer. They are fundamental requirement of any language. Each language has its own rules for naming these identifiers.

To name the variables of your program, you must follow strict rules. In fact, everything else in your program must have a name.

There are some rules you must follow when naming your objects. On this site, here are the rules we will follow:

• The name must start with a letter or an underscore or the at symbol @.

• After the first letter or underscore, the name can have letters, digits, and/or underscores.

• The name must not have any special characters other than the underscore.

• The name cannot have a space.

• It should not a keyword.

C# is case-sensitive. This means that the names Case, case, and CASE are completely different. For example, the main function is always written Main.

FEATURES OF C#

Simplicity

All the Syntax of java is like C++. There is no preprocessor and much larger library. C# code does not require header files. All code is written inline.

Consistent Behavior

C# introduced a unified type system which eliminates the problem of varying ranges of integer types. All types are treated as objects and developers can extend the type system simply and easily.

Modern Programming Language

C# supports number of modem features, such as:

• Automatic Garbage Collection

• Error handling features

• Modern debugging features

• Robust Security features

Pure Object-Oriented Programming Language

In C#, every thing is an object. There are no more global functions, variable and constants.

It supports all three object oriented features:

• Encapsulation

• Inheritance

• Polymorphism

How to Comparing C# to C++ and Java

Microsoft Corporation developed a new computer programming language C# pronounced as 'C- Sharp'. C# is a simple, modem, object oriented, and type safe programming language derived from C and C++. C# is a purely object-oriented language like as Java. It has been designed to support the key features of .NET framework. Like Java, C# is a descendant language of C++ which is descendant of C language.

What is Visual Studio.NET

What is Visual Studio.NET

Many people always get confused with Visual Studio .NET (VS.NET) and .NET technology. VS.NET is just an editor, provided by Microsoft to help developers to write .NET programs easily. VS.NET editor automatically generates lot of code, allow developers to drag and drop controls to a form, provide short cuts to compile and build the application etc.

VS.NET is not a required thing to do .NET programming. You can simply use a notepad or any other simple editor to write your .NET code. And you can compile your .NET programs from the command prompt. Well, what we said is true theoretically but if you decide to use notepad for .NET programming, by the time you develop few sample applications, Microsoft would have introduced some other new technology and .NET would be outdated. You may not want that. So, let us go by VS.NET, because it makes things much easier for us.

The following is the list of some of the features of Visual Studio .NET:

1. Visual studio automates the step required to compile source code.

2. The Visual Studio text editor is very intelligent; it can detect errors and suggests code as appropriate as you required.

3. The Visual Studio designer for Windows Forms and Web Forms applications, allowing simple Drag and drop design of User Interface elements.

4. The Visual Studio contains many powerful tools for visualizing and navigating through the elements of our projects, whether they are C# code files or other resources such as bitmap images or sound files.

5. The Visual Studio enables us to use advance debugging techniques when developing projects, such as ability to step through code one instruction at a time while keeping an eye on the state of our application.

WORKING WITH VISUAL STUDIO .NET

Visual Studio is a very user friendly tool. But there is enough stuff to confuse anyone new to Visual Studio family. The purpose of this section is to make you familiar with different options in Visual Studio.NET (VS.NET) We will not cover the entire visual studio guide. We are just explaining the most commonly used features of VS.NET.

When you work on any project, VS.NET has several child windows to assist you in the application development. These windows are attached on the left, bottom and right sides of the main window. You can click on these small windows to expand it and see the content of them. Some of the most commonly used child windows are explained below. Most of these windows will be enabled only when you have created a project and working on a WebForm/ WinForm.

Toolbox

Toolbox provides all the drag and drop controls for your application. Depending on the kind of application you are working on, the toolbox will show appropriate controls and you can drag and drop them to your form. If you are developing a web application, toolbox will. Show ASP .NET controls and if you are developing a Windows application, it will show Windows controls (like Radio button, text box, buttons etc).

You can simply drag and drop any controls from the toolbox to your form. After you drag and drop any control, double click on the control to go the default event associated with the control.

The Toolbox will be enabled only when you have a WebForm or WinForm opened in Design mode and is usually located on TOP LEFT corner of the VS.NET.

By default, all windows including Toolbox will be displayed as Minimized (Marked as A in figure). You will see only the small icon and the text 'Toolbox' written vertically on the left bar of VS.NET. You can click on this minimized window to expand it (Expanded window is marked as C in figure). When you move the mouse away from the window, it will again automatically minimize. You can keep the toolbox always expanded by pressing the pushpin.

                   

The above behavior is common for all the windows explained below. They will be minimized by default and you can point the mouse over it to expand it. Use the pushbutton to keep it expanded.

Design mode & HTML mode

If you are developing a web application, you can switch between design mode and HTML mode for any web form. When you are in HTML mode, it will show you the HTML tags and ASP.NET code and you can manually edit it. You can switch to the Design mode by clicking the Design button on BOTTOM LEFT corner ofVS.NET (see figure). In design mode, you can see how your ASP.NET page is going to look like when some one views your web page. Also, you can drag and drop controls from the toolbox, which will automatically generate the HTML for it.

Typically, developers switch between these two modes very frequently. You can go to design mode to drag/drop controls, right click on the controls to set correct properties etc. Then, click on the HTML mode to view the generated HTML. You can manually make changes to the automatically generated HTML. If you change any properties in HTML mode, the changes will be reflected when you switch to Design Mode.

                        

Solution. Explorer

Solution Explorer, located on TOP RIGHT corner of VS.NET, displays your solution, all projects included in each solution and the list of files in each project. They are listed in the form of a tree control.

Typically, for a single application, you will have 1 solution and one or more projects. When you create a new application, you have to create single Visual Studio project. In more complex applications, there may be more than one projects. All these projects are grouped into a single solution. Even if you do not create a solution separately, a solution will be automatically created for you.

                 

To add a new file to your project, you can right click on the project name (Just Test is the project name in the figure) and choose the menu option Add. It will give you the option to choose a file type. You can choose an appropriate type.

For Winforms and WebForms you can see-the file in design mode-and the code associated with it. Double click on any form and it will,-be opened in design mode. Right click on' any form and select the menu option 'View Code' to view the--code associate with the form.

Output

Output window, located on BOTTOM LEFT corner ofVS.NET, displays the result of your project compilation. When you compile your project, all errors, warnings and compilation results will be displayed in this window.

                         

In addition to the Output window, they are few other windows located in the BOTTOM

LEFT corner of VS.NET.

Task List

Shows individual tasks. Typically, when you compile your project, all errors and warnings will be added to your task list. You can double click on any item in the task list to go directly to the code associated with the task.

Command Window

You can execute code statements here. When you are debugging, you can evaluate the' value of any variables by typing? Followed by the variable name.

Find Results

When you search for any text in file(s) using VS.NET, the results will be displayed in this window.

Projects

VS.NET allows you to create several types of projects. Most of the time you will be using one of two categories:

• Windows Application - to create any standard windows application.
• ASP.NET Web Application - to create a web site.

Creating a Project

To create a new project, choose the main menu : File > New > Project.

It will give you several options. First you must select a type from the left side of the popup. You may choose Visual Basic Projects or Visual C# projects based on the language you plan to use for development. -

After selecting a type, you choose a template from the right side. You may choose Windows Application, ASP.NET Web Application or any other template based on the nature of the application you want.

When you create a Windows Project or ASP.NET Web Project, VS.NET will add a sample file by default. You can simply Build your new project and see how it works.

Building a project

To try this, create a new Windows Project as explained above. It will create a sample form. Go to the main menu and select the menu item Build> .Build Solution.

This process will compile all the files included in your project and show you the result in the Outputwindow. If the result shows '0 failed', your build is success and your application is ready to deliver!!

To Run the application you just Built, go to the main menu and select Debug > Start without debugging. This will launch the application you just developed.

You drag and drop several controls to the form and try running it.

When you compile (build) the code, if there- is any errors or warnings, the details will be shown in the 'Task List' window. You can click on the specific item in this window to go directly to the line of code associated with the error.

                       

Type of .NET Languages

Type of .NET Languages :

To help create languages for the .NET Framework, Microsoft created the Common Language Infrastructure specification (CLI). The CLI describes the features that each language must provide in order to use the .NET Framework and comm6n language runtime and to interoperate with components written in other languages. If a language implements the necessary functionality, it is said to be .NET-compliant.

Every .NET-compliant language supports the same data types, uses the same .NET Framework classes, compiles to the same MSIL, and uses a single common language runtime to manage execution. Because of this, every .NET-compliant language is a first-class Microsoft .NET citizen.-Developers are free to choose the best language for a particular component without losing any of the power and freedom of the platform. In addition, components written in one language can easily interoperate with components written in another language. For example, you can write a class in C# that inherits from a base class written in Visual Basic.

The .NET Framework was developed so that it could support a theoretically infinite number of development languages. Currently, more than 20 development languages work with the .NET Framework. C# is the programming language specifically designed for the .NET platform, but C++ and Visual Basic have also been upgraded to fully support the .NET framework. The following are the commonly used languages provided by the Microsoft:

• VC++

• VB.NET

.C#

• J#

• JScript .NET 

Many third parties are writing compilers for other languages with .NET support. With CLR, Microsoft has adopted a much liberal policy. Microsoft has them selves evolved/ developed/ modified many of their programming languages which compliant with .NET CLR.

VC++

Although Visual C++ (VC++) , has undergone changes to incorporate .NET; yet VC++ also maintains its status being a platform dependent programming. Many new MFC classes have been added a programmer can choose between using MFC and compiling the program into a platform specific executable file; or using .NET framework classes and compile into platform independent MISL file. A programmer can also specify (via directives) when ever he uses "unsafe" (the code that by passes CLR, e.g. the use of pointers) code.

VB.NET

Out of ALL .NET languages, Visual Basic.NET (VB.NET) is one language that has probably undergone into the most of changes. Now VB.NET may be considered a complete Object- Oriented Language (as opposed to its previous "Half Object Based and Half Object Oriented" status).

Visual Basic .NET provides substantial language innovations over previous versions of visual basic. Visual Basic .NET supports inheritance, constructors, polymorphism, constructor overloading, structured exceptions, stricter type checking, free threading, and many other features. There is only one form of assignment: noLet of set methods. New rapid application development (BAD) features, such as XML Designer, Server Explorer, and Web Forms designer, are available in Visual Basic from Visual Studio .NET. With this release, Visual Basic Scripting Edition provides full Visual Basic functionality.

C# 

Microsoft has also developed a brand new programming language C# (C Sharp). This language makes full use of .NET. It is a pure object oriented language. A Java programmer may find most aspects of this language which is identical to Java. If you are a new comer to Microsoft Technologies - this language is the easiest way to get on the .NET band wagon. While VC++ and VB enthusiast would stick to VC.NET and VB.NET; they would probably increase their productivity by switching to C#. C# is developed to make full use of all the intricacies of .NET. The learning curve of C# for a Java programmer is minimal. Microsoft has also come up with a The Microsoft Java Language Conversion Assistant-which is a tool that automatically converts existing Java-language source code into C# for developers who want to move their existing applications to the Microsoft .NET Framework.

J#

Microsoft has also developed J# (Java Sharp). C# is similar to Java, but it is not entirely' identical. It is for this reason that Microsoft has developed J# - the syntax of J# is identical to Visual J++. Microsoft's growing legal battle with Sun, over Visual J++ - forced Microsoft to discontinue Visual J++. So J# is Microsoft's indirect continuation of Visual J++. It has been reported that porting a medium sized Visual J++ project, entirely to J# takes only a few days of effort.

JScript.NET 

Jscript.NET is rewritten to be fully .NET aware. It includes support for classes, inheritance, types and compilation, and it provides improved performance and productivity features. JScript.NET is also integrated with visual Studio .NET. You can take advantage of any .NET Framework class in JScript .NET.

Third-party languages

Microsoft encourages third party vendors to make use of Visual Studio. Net. Third, party vendors can write compilers for different languages ~ that compile the language to MSIL

(Microsoft Intermediate Language). These vendors need not develop their own development environment. They can easily use Visual Studio.NET as an IDE for their .NET compliant language. A vendor has already produced COBOL.NET that integrates with Visual Studio.NET and compiles into MSIL. Theoretically it would then be possible to come up with Java compiler that compiles into MSIL, instead of Java Byte code; and uses CLR instead of JVM. However Microsoft has not pursued this due to possible legal action by Sun.

Several third party languages are supporting the .NET platform. These languages include APL, COBOL, Pascal, Eiffel, Haskell, ML, Oberon, Perl, Python, Scheme and Smalltalk.

What is Dot Net Framework?

What is Dot Net Framework?

Microsoft officially defined .NET Framework as follows:

The .NET Framework is the heart of Microsoft .NET. The .NET Framework is a software development platform of Microsoft .NET. Like any platform, it provides a runtime, defines functionality in some libraries, and supports a set of programming languages. The .NET Framework provides the necessary compile-time and run-time foundation to build and run .NET-based applications.

            

The .NET Framework consists of:

• Common Language Runtime

• Class Libraries

• Support for Multiple Programming Language 

The common language runtime (CLR) (also refer as runtime). The Common Language

Runtime is the core of Microsoft's .NET vision. This is said to be the execution engine of .NET platform. The runtime (CLR) handles runtime services, including language integration, security, and memory management. During development, the runtime (CLR) provides features that are needed to simplify development.

Class libraries: Class libraries provide reusable code for most common tasks, including data access, XML Web service development, and Web and Windows Forms. The CLR Software Development Kit (SDK) provides the programming APIs in the form of a set of classes for building .NET applications. Collectively, they are referred to the Base Class Library, or BCL.

Through the classes in the BCL, we can interact with the runtime, influencing the way that the runtime's services are provided to us. In addition to giving us an "in" to the runtime, the BCL classes provide a large number of useful utilities. These include things like a new database access library (ADO.NET), ASP.NET, and an XML parser with support for the latest XML specifications. In addition, developers can extend classes by creating their own libraries of classes. All applications (Web, Windows, and XML Web services) access the same .NET Framework class libraries, which are held in namespaces.

Support for multiple programming languages. Having a set of libraries and a runtime is good, but neither one of them is useful if you can't write programs to take advantage of them. In order to do that, you need to use some programming language with a compiler that is runtime-aware. Microsoft currently lists over twenty different languages with which it will be possible to write software that targets the CLR. Microsoft itself ship support for five languages with the SDK: C#, Visual Basic.NET, IL, C++, and JScript.NET. Of these, C# and Visual Basic.NET are likely to be the languages most often used to develop software for this new platform. Any language that conforms to the Common Language Specification (CLS) can run with the common language runtime. Relying on the common language runtime, code compiled with compilers of .NET based languages can interoperate. All .NET-based languages also access the same libraries.

Features of .NET Framework 

• It is a platform neutral framework.

• It is a layer between the operating system and the programming language.

• It supports many programming languages, including VB.NET, C# etc.

• .NET provides a common set of class libraries, which can be accessed from any .NET based programming language. There will not be separate set of classes and libraries for each language. If you know anyone .NET language, you can write code in any .NET language.

• In future versions of Windows, .NET will be freely distributed as part of operating system and users will never have to install .NET separately.

Application Development and Execution 

Developing application:

Since Microsoft .NET is a Multilanguage platform then any.NET based language can be chosen to develop applications. Comfort ability of application programmers, specific requirement of applications may be the major factors in selection of language.

Choosing a Compiler

According to the language we can choose its run time aware compiler for .NET platform. Because it is a Multilanguage execution environment, the runtime supports a wide variety of data types and language features.

Compiling to MSIL

When compiling your source code, the compiler translates it into an intermediate code represented in Microsoft intermediate language (MSIL). Before code Can be run, MSIL code must be converted to CPU-specific code, usually by a just-in-time (JIT) compiler. When a compiler produces MSIL, it also produces metadata. Metadata includes following information.

• Description of the types in your code, including the definition of each type,

• The signatures of each type's members,

• The members that your code references,

• Other data that the runtime uses at execution time.

The MSIL and metadata are contained in a portable executable (PE) file that is based on and extends the published Microsoft PE and common object file format (COFF) used historically for executable content. This file format, which accommodates MSIL or native code as well as metadata, enables the operating system to recognize common language runtime images.

                         

The presence of metadata in the file along with the MSIL enables your code to describe itself. This composite file serves as a self describing unit to the .NET Framework Runtime is called Assembly. The runtime locates and extracts the metadata from the file as needed during execution.

JIT Compilation to Native code:

The MSIL code is compiled into native code by component of CLR named JIT Compiler.

JIT compiler intelligently guesses and compiles the intermediate code on piece by piece basis. This piece may be a method or a set of methods. Before a method can be run, it must be compiled to processor-specific code. Each method for which Microsoft intermediate language (MSIL) has been generated is just-in-time-compiled (JIT-compiled) when it is called for the first time, and then run. The next time the method is run, the existing JIT -compiled native code is run. The process of JIT -compiling and then executing the code is repeated until execution is complete.

Type Safety Checking

As part of compiling MSIL to native code, code must pass a verification process unless an administrator has established a security policy that allows code to bypass verification. Verification examines MSIL and metadata to find out whether the code is type safe, which means that it only accesses the memory locations it is authorized to access. Additionally, verification inspects code to determine whether the MSIL has been correctly generated, because incorrect MSIL can lead to a violation of the type safety rules .

The runtime relies on the fact that the following statements are true for code that is verifiably type safe:

• A reference to a type is strictly compatible with the type being referenced.

• Only appropriately defined operations are invoked on an object.

• Identities are what they claim to be.

If type-safe code is required by security policy and the code does not pass verification, an exception is thrown when the code is run.

Code execution under CLR

The common language runtime is responsible for providing following low-level execution services, such as garbage collection, exception handling, security services, and runtime type safety checking. Because of the common language runtime's role in managing execution, programs that target the .NET Framework are sometimes called "managed" applications.

I am learning .NET. Do you want to learn? then What is .NET?

INTRODUCTION

The .NET is the technology from Microsoft, on which all other Microsoft technologies will be depending on in future. It is a major technology change, introduced by Microsoft, to catch the market from the SUN's Java. Few years back, Microsoft had only VC++ and VB to compete with Java, but Java was catching the market very fast. With the world depending more and more on the Internet/ Web and java related tools becoming the best choice for the web applications, Microsoft seemed to be loosing the battle. Thousands of programmers moved to java from VC++ and VB. To recover the .market, .Microsoft announced .NET.

But Microsoft has a wonderful history of starting late but catching up quickly. This is true in case of .NET too. Microsoft put their best men at work for a secret project called Next Generation Windows Services (NGWS)., under the direct supervision of Mr. Bill Gates.

The outcome of the project is what we now know as .NET. Even though .NET has borrowed most of it's ideas from Sun's J2EE, it has really outperformed their competitors.

Microsoft's VC++ was a powerful tool. But it was too complex. It has too many data types, and developers had to learn many libraries including Windows SDK, MFC, ATL, COM etc. There were many data type compatibility issues while exchanging data between different layers. Visual Basic was too easy, and many serious programmers hated it just for that reason. Even though Visual basic was very easy to use, it was not very flexible to develop serious applications. SUN's Java became a very good choice for these reasons. It had the flexibility and power of C++ and at the same time easy enough to catch the attention of VB programmers.

Microsoft recognized these factors and they introduced the .NET considering all these factors. All unwanted complexities are eliminated and a pure object oriented programming model was introduced. This makes programmer's life very easy.

.NET is said to be Microsoft development model in which software becomes platform and device independent and data becomes available over the internet. Due to this vision Microsoft .NET is also called Microsoft strategy for connecting systems, information and devices through web services so people can collaborate and communicates effectively.

The Microsoft .NET vision

The idea that all devices will some day be connected by a global broadband network

(Internet) and that software will become service provided over this network. ".NET" has been applied to everything from the next version of the Windows operating system to development tools.

Major Problems before .NET:

The following are the major problems in previous Microsoft Technologies faced by the developers for application development and deployment, which has been solved by the .NET:

Registration of COM components. COM components had to be registered on the target machine before they could be used by the application. The application had to look up the Windows registry to locate and load the COM components.

• Unloading COM components. COM objects also required a special logic for freeing up the objects from memory. This method is known as reference counting of COM objects. It is used to keep track of the number of active references. When an object's reference count reaches zero, the object is removed from memory. The major problem that arises out of this situation is that of circular reference. If circular references exist between two COM components, they would not be freed from memory.

• Versioning Problem (DLL hell). Whenever applications that use COM components were installed on a machine, the installation process would update the registry with the COM components information. Thus, there was a chance that these DLLs would be overwritten when some other applications were installed on the same computer. Therefore, an application that had been referring to one particular DLL would refer to the wrong DLL. This caused a major problem when an application was referring to particular version of a DLL.

THE .NET PLATFORM

The .NET platform is a set of technologies. Microsoft .NET platform simplify software development (Windows or WEB) by building applications of XML Web services.

The.NET platform consists of the following core technologies:

• The .NET Framework

• The .NET Enterprise Servers

• Building block services

• Visual Studio .NET

                         

A programming model (.NET Framework) that enables developers to build Extensible Markup Language (XML) Web services and applications.

A set of .NET Enterprise Servers, including Windows 2000, Microsoft SQL Server., and Microsoft BizTalk® Server, that integrate, run, operate, and manage XML Web services and applications.

The .NET Framework must run on an operating system. Currently, the .NET Framework is built to run on the Microsoft Win32® operating systems, such as' Windows 2000, Windows XP, and Windows 98. When .NET Framework running on Windows 2000 then application services (such as Component Services, Message Queuing, Internet Information Services (IIS), and Windows Management Instrumentation (WMI) ) are available to the developers. The .NET Framework exposes application services through classes in the .NET Framework class library.

There are some client software such as Windows XP and Windows CE, which helps developers deliver a comprehensive user experience across a family of devices. A set of building block services that are a user-centric set of XML Web services that move control of user data from applications to users. For example, Microsoft Passport is a core component of the .NET initiative that makes it easier to integrate various applications.

XML Web services are programmable Web components that can be shared among applications on the Internet or the intranet. The .NET Framework provides tools and classes for building, testing, and distributing XML Web services.

Visual Studio .NET is a tool, which can be used to develop XML Web services and

Windows and Web applications for an enriched user experience.