.NET FRAMEWORK, Feature of .NET , clr?
.NET is the greatest invention from Microsoft which is developed by the Microsoft corporation .....The Microsoft .NET Framework is a software framework that can be installed on computers running Microsoft Windows operating systems. It includes a large library of coded solutions to common programming problems and a virtual machine that manages the execution of programs written specifically for the framework....The purpose of launching .net framework is to offer a platform to be used by most new application created for windows....Net framework covers large range of programming needs including user interface, dataaccess ,connectivity etc.....NET framework is included with server 2003, windows server 2008 and windows vista and can be installed on older version of windows like windows XP...
Clr: . The CLR provides the appearance of an application virtual machine so that programmers need not consider the capabilities of the specific CPU that will execute the program. The CLR also provides other important services such as security, memory management, and exception handling. Developers using the CLR write code in a language such as C# or VB.NET. At compile time, a .NET compiler converts such code into Common intermediate language code. i. e. At runtime, the CLR's just-in-time compiler converts the CIL code into code native to the operating system.......
Features of clr:
Features of .NET framework:
1. Common Runtime Engine: The Common Language Runtime (CLR) is the virtual machine component of the .NET framework. All .NET programs execute under the supervision of the CLR, guaranteeing certain properties and behaviors in the areas of memory management, security, and exception handling.
2. Security: The design is meant to address some of the weakness, such as buffer overflows, that have been gain by malicious software. Additionally, .NET provides a common security model for all applications.
3. Simplified Deployment: The .NET framework includes design features and tools that help manage the installation of computer software to ensure that it does not interfere with previously installed software, and that it conforms to security requirements.
4. Language Independence: The .NET Framework introduces a Common Type System, or CTS. The CTS specification defines all possible data types and programming constructs supported by the CLR and how they may or may not interact with each other.
5. Base Class Library: The Base Class Library (BCL), part of the Framework Class Library (FCL), is a library of functionality available to all languages using the .NET Framework. The BCL provides classes which encapsulate a number of common functions, including file reading and writing, graphic rendering, database interaction and XML document manipulation.
Clr: . The CLR provides the appearance of an application virtual machine so that programmers need not consider the capabilities of the specific CPU that will execute the program. The CLR also provides other important services such as security, memory management, and exception handling. Developers using the CLR write code in a language such as C# or VB.NET. At compile time, a .NET compiler converts such code into Common intermediate language code. i. e. At runtime, the CLR's just-in-time compiler converts the CIL code into code native to the operating system.......
Features of clr:
- CLR manages memory, thread execution, code execution, compilation code safety verification and other system services.
- CLR eliminates many common software issues like handling of object layout, references to objects and garbage clearance. This type of memory management prevents memory leaks and invalid memory references.
- The CLR also accelerates developer productivity. The programmer is free to choose the language of the application without worrying about compatibility and integration issues.
- The Common Type System (CTS) defines the rules concerning data types and ensures that code is executed in a safe environment.
Features of .NET framework:
1. Common Runtime Engine: The Common Language Runtime (CLR) is the virtual machine component of the .NET framework. All .NET programs execute under the supervision of the CLR, guaranteeing certain properties and behaviors in the areas of memory management, security, and exception handling.
2. Security: The design is meant to address some of the weakness, such as buffer overflows, that have been gain by malicious software. Additionally, .NET provides a common security model for all applications.
3. Simplified Deployment: The .NET framework includes design features and tools that help manage the installation of computer software to ensure that it does not interfere with previously installed software, and that it conforms to security requirements.
4. Language Independence: The .NET Framework introduces a Common Type System, or CTS. The CTS specification defines all possible data types and programming constructs supported by the CLR and how they may or may not interact with each other.
5. Base Class Library: The Base Class Library (BCL), part of the Framework Class Library (FCL), is a library of functionality available to all languages using the .NET Framework. The BCL provides classes which encapsulate a number of common functions, including file reading and writing, graphic rendering, database interaction and XML document manipulation.
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Q.....Msil, common type system garbage collector?
MSIL stands for microsoft intermediate language also knows as common intermediate language ....It acts as a bridge between the operating system and the application...Common intermediate language is the lowest level human readable programming language in the common language infrastructure and in .NET framework...During the compilation of .NET programming language the source code is translated into CIL code rather than platform or processor specified code..CIL is a cpu and platform-independent instruction set, that can be executed in any environment supporting the .net framework..CIL code is verified during runtime, provide better security and reliability ...
Common type system: The common type system defines how types are declared, used, and managed in the runtime, and is also an important part of the runtime's support for cross-language integration. The common type system performs the function like
Garbage collector: CLR also contains Garbage Collector (GC) which runs in a low-priority thread and checks for un-referenced dynamically allocated memory space. If it finds some data that is no more referenced by any variable/reference, it re-claims it and returns the occupied memory back to the Operating System; so that it can be used by other programs as necessary. The presence of standard Garbage Collector frees the programmer from keeping track of dangling data.
Common type system: The common type system defines how types are declared, used, and managed in the runtime, and is also an important part of the runtime's support for cross-language integration. The common type system performs the function like
- Establishes a framework that helps enable cross-language integration, type safety, and high performance code execution.
- Provides an object-oriented model that supports the complete implementation of many programming languages.
- Defines rules that languages must follow, which helps ensure that objects written in different languages can interact with each other.
Garbage collector: CLR also contains Garbage Collector (GC) which runs in a low-priority thread and checks for un-referenced dynamically allocated memory space. If it finds some data that is no more referenced by any variable/reference, it re-claims it and returns the occupied memory back to the Operating System; so that it can be used by other programs as necessary. The presence of standard Garbage Collector frees the programmer from keeping track of dangling data.
Q.....VB6 vs VB.Net...
- one of the greatest feature of .net framework is the ability to create multithreaded application in visual basic without having to use third party tools or unsupported visual basic tricks which was not at all possible in VB..
- VB.NET is a true oriented programming language whereas VB was not..
- The greatest change in VB6 and VB.NET is of runtime environment. VB6 used the VB-Runtime while VB .NET uses to the Common Language Specification (CLS) for language interoperability which is also shared with C#.
- VB6 used the ‘On Error Goto’ syntax to handle exceptions at runtime. VB.NET uses the Try…Catch…Finally syntax to handle exceptions at runtime.
- A lot of code (like user interface code) in VB6 was hidden from developer. In VB.NET no code is hidden from developer and you can access and control each part of your application and it now has C-like Syntax
- Arrays is 0 based in VB .NET. i.e when you declare an array in vb6 "Dim Items(5) As String" you would get an array with 6 elements but in VB.NET it would be 5 items now.
- VB6 was only considered good for desktop windows application. In VB.NET you can develop web applications, distributed applications, create .NET windows and web controls and components, write windows and web services.
- Components created in VB6 (COM) need to make and update registry entries. VB.NET does not require any registry entry making the deployment easier
Q...VB.net vs Java
- Java is from Sun, .Net is from Microsoft
- Java is a language plus a runtime, .Net is a runtime framework that supports multiple languages, Visual Basic and C# (the .Net language most similar to Java) among them.
- java is more platform independent, it runs on several operating systems including Windows, Mac and Linux. .Net is primarily for Windows.
- .Net has a more integrated development environment, as the IDE, runtime and server all come from Microsoft as a standard package, while Java is based on third-party tool and server providers.
Q.....Vb.net vs C#
- In C#, using keyword is used to release unmanaged resources. (Not available in VB.NET)
- Optional parameter is supported in VB.NET. (Not available in C#).
- Structure and unstructured error handling (On Error GoTo) is supported in VB.NET. (Unstructured error handling is not supported in C#).
- VB.NET is not case sensitive where C# is.
- c# support unsafe code blocks, anonymous method, multiline comments but the are not available in VB...
- keyword are very different between two language . Like "me: in vb.net is used as "this" in c#...
- One main difference between both is in blocks...VB terminates a block code with end blockName..In c# the use of brackets ,{} will be more familiar to programmers...
Q........Net architecture..
The .Net Framework is an inbuilt windows component that supports Building and running the next generation of application xml web services. The .Net Framework has been developed to fulfill to the following objectives and Requirements:
- To provide a consistent object-oriented environment to develop applications;
- To provide a code execution environment that simplifies deployment ..
- Language becomes a matter of choice.
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ASP.NET: ASP.net helps use to allow to developing websites ...It fulfills all the requirements which are needed in website development..ASP.NET is a part of .NET famework which is used to build dynamic web sites, web applications and web services.
VB.NET: VB.NET allows user to create a application form using visual studio application...It contains many tools like textboxes , labels , picture boxes etc...VB.NET is built on the Common Language Runtime (CLR) allowing programmers to write ASP.NET code using any supported .NET langauge..
C#: A hybrid of C and C++, it is a Microsoft programming language developed to compete with Sun's Java language. C# is an object-oriented programming language used with XML-based Web services on the .NET platform and designed for improving productivity in the development of Web applications...
J#: J# is Microsoft's implementation of the Java programming language. It is specifically designed to allow Java-language developers to easily transition to the .NET Framework and to create .NET applications.
CLS : CLS is a type of platforms that converts many types of language in to common intermediate language which is understandable for CLR to run the following coding....it support all the coding done in VB.Net , asp.net , C# and J# etc...
Class library : .NET Framework provides huge set of Framework (or Base) Class Library (FCL) for common, usual tasks. FCL contains thousands of classes to provide the access to Windows API and common functions like String Manipulation, Common Data Structures, IO, Streams, Threads, Security, Network Programming, Windows Programming, Web Programming, Data Access, etc. It is simply the largest standard library ever shipped with any development environment or programming language.
Clr: . The CLR provides the appearance of an application virtual machine so that programmers need not consider the capabilities of the specific CPU that will execute the program. The CLR also provides other important services such as security, memory management, and exception handling. Developers using the CLR write code in a language such as C# or VB.NET. At compile time, a .NET compiler converts such code into Common intermediate language code.
Common type system: The common type system defines how types are declared, used, and managed in the runtime, and is also an important part of the runtime's support for cross-language integration. The common type system performs the function like, establishes a framework that helps enable cross-language integration, type safety, and high performance code execution.
METADATA: Metadata is binary information describing your program that is stored either in a common language runtime portable executable (PE) file or in memory. When you compile your code into a PE file, metadata is inserted into one portion of the file, while your code is converted to Microsoft intermediate language (MSIL) and inserted into another portion of the file. When code is executed, the runtime loads metadata into memory and references it to discover information about your code's classes, members, inheritance, and so on.
VB.NET: VB.NET allows user to create a application form using visual studio application...It contains many tools like textboxes , labels , picture boxes etc...VB.NET is built on the Common Language Runtime (CLR) allowing programmers to write ASP.NET code using any supported .NET langauge..
C#: A hybrid of C and C++, it is a Microsoft programming language developed to compete with Sun's Java language. C# is an object-oriented programming language used with XML-based Web services on the .NET platform and designed for improving productivity in the development of Web applications...
J#: J# is Microsoft's implementation of the Java programming language. It is specifically designed to allow Java-language developers to easily transition to the .NET Framework and to create .NET applications.
CLS : CLS is a type of platforms that converts many types of language in to common intermediate language which is understandable for CLR to run the following coding....it support all the coding done in VB.Net , asp.net , C# and J# etc...
Class library : .NET Framework provides huge set of Framework (or Base) Class Library (FCL) for common, usual tasks. FCL contains thousands of classes to provide the access to Windows API and common functions like String Manipulation, Common Data Structures, IO, Streams, Threads, Security, Network Programming, Windows Programming, Web Programming, Data Access, etc. It is simply the largest standard library ever shipped with any development environment or programming language.
Clr: . The CLR provides the appearance of an application virtual machine so that programmers need not consider the capabilities of the specific CPU that will execute the program. The CLR also provides other important services such as security, memory management, and exception handling. Developers using the CLR write code in a language such as C# or VB.NET. At compile time, a .NET compiler converts such code into Common intermediate language code.
Common type system: The common type system defines how types are declared, used, and managed in the runtime, and is also an important part of the runtime's support for cross-language integration. The common type system performs the function like, establishes a framework that helps enable cross-language integration, type safety, and high performance code execution.
METADATA: Metadata is binary information describing your program that is stored either in a common language runtime portable executable (PE) file or in memory. When you compile your code into a PE file, metadata is inserted into one portion of the file, while your code is converted to Microsoft intermediate language (MSIL) and inserted into another portion of the file. When code is executed, the runtime loads metadata into memory and references it to discover information about your code's classes, members, inheritance, and so on.
Q......Web Browser & Web server?
Programming is the intricate art of telling a computer what to do. Programming is giving written instructions in a logical manner that the computer can understand. Essentially, you give the computer small steps of instructions, and the computer execute each one in order. Programming allows you to make new software and have the computer do new things. Web site programming is the same except you write applications or web pages that are used by a web browser..... Web Site Programming is the practice of writing applications that run on a web server and can be used by many different people. Many applications work really well as a web application. Some examples of popular web applications include Flickr, Gmail, and Google Maps. You are able to upload and view pictures, send email and lookup directions using these web applications and they are all made possible through web site programming. Some web programming language include HTML, asp.Net, JSP , Pearl...
CLICK HERE
WEB BROWSER
WEB SERVER
CLICK HERE
WEB BROWSER
WEB SERVER
How .NET is used as website development?
IN .NET programming ASP.net helps use to allow to developing websites ...It fulfills all the requirements which are needed in website development..ASP.NET is a part of .NET famework which is used to build dynamic web sites, web applications and web services. ASP.NET is built on the Common Language Runtime (CLR) allowing programmers to write ASP.NET code using any supported .NET langauge...A Microsoft server-side Web technology. ASP.NET takes an object-oriented programming approach to Web page execution. Every element in an ASP.NET page is treated as an object and run on the server. An ASP.NET page gets compiled into an intermediate language by a .NET Common Language Runtime-compliant compiler......Some features of using asp.net
1. Better language support
2. User authentication
3. Increase performance..
4. Easy to upgrade..
5. High level security..etc..
1. Better language support
2. User authentication
3. Increase performance..
4. Easy to upgrade..
5. High level security..etc..
.NET base classes...
System.Object is the base class of .NET..... It Supports all classes in the .NET Framework class hierarchy and provides low-level services to derived classes. This is the ultimate superclass of all classes in the .NET Framework; it is the root of the type hierarchy...Base class is a root class or superior class from which we can extend classes. Base class is the topmost in the classes so other classes can be derived from this class but it is not derived from any class.Depending on procedure base class may or may not give its objects to derived classes of it.
Assemblies & Base class library....
Assemblies are building blocks of .NEt framework application, the form a fundamental unit of deployment ,version control ,reuse, activation scoping , and security permission...An assembly is a collection of types and resources that are built to work together and form a logical unit of functionality...An assembly provide the common language runtime with the information it needs to be of type of implementation....An assembly perform the following functions:
Assemblies can be static and dynamic..Static assemblies include .NEt framework types (interface and classes) as well as resources for the assembly (bitmaps files, jpeg files )....Static assemblies are stored in Portable executable files.. YOu can also use .net framework to create dynamic assemblies, which are run directly from memory and are not saved to disk before execution....
Class library : .NET Framework provides huge set of Framework (or Base) Class Library (FCL) for common, usual tasks. FCL contains thousands of classes to provide the access to Windows API and common functions like String Manipulation, Common Data Structures, IO, Streams, Threads, Security, Network Programming, Windows Programming, Web Programming, Data Access, etc. It is simply the largest standard library ever shipped with any development environment or programming language. The best part of this library is they follow extremely efficient design (design patterns) making their access and use very simple and predictable. You can use the classes in FCL in your program just as you use any other class and can even apply inheritance and polymorphism on these.
- It contains the code that the common language runtime executes ...Microsoft Intermediate language code in portable executable will no be executed if it does not have a associated manifest...
- In assemblies the permission are requested and granted...
- It is the unit at which side by side execution is supported...
- It forms a deployment unit ...When a application starts only the assemblies that the application initially calls must be present....Other assemblies such as localization resources can be retrieved on demand....
Assemblies can be static and dynamic..Static assemblies include .NEt framework types (interface and classes) as well as resources for the assembly (bitmaps files, jpeg files )....Static assemblies are stored in Portable executable files.. YOu can also use .net framework to create dynamic assemblies, which are run directly from memory and are not saved to disk before execution....
Class library : .NET Framework provides huge set of Framework (or Base) Class Library (FCL) for common, usual tasks. FCL contains thousands of classes to provide the access to Windows API and common functions like String Manipulation, Common Data Structures, IO, Streams, Threads, Security, Network Programming, Windows Programming, Web Programming, Data Access, etc. It is simply the largest standard library ever shipped with any development environment or programming language. The best part of this library is they follow extremely efficient design (design patterns) making their access and use very simple and predictable. You can use the classes in FCL in your program just as you use any other class and can even apply inheritance and polymorphism on these.
COM
Component Object Model is a model that allows different programming languages to communicate each other....
User Interface...
User interface plays and important role in computer.....It is a Visual part of computer application or operating system through which a user interacts with a computer or a software. It determines how commands are given to the computer or the program and how information is displayed on the screen. Three main types of user interfaces are (1) Command language: the user must know the machine and program-specific instructions or codes. (2) Menus: user chooses the commands from lists displayed on the screen. (3) Graphical user interface (GUI): user gives commands by selecting and clicking on icons displayed on the screen.....It is very necessary for a programmer to provide a simple interface while creating a software or developing software because it makes easy for a user to run that software and work on it......Things to be consider a good user interface needs to be
- Clear :Clarity is the most important element of user interface design. The whole purpose of user interface design is to enable people to interact with your system by communicating meaning and function...
- Consistent: Consistent interfaces allow users to develop usage patterns -- they'll learn what the different buttons, tabs, icons and other interface elements look like and will recognize them and realize what they do in different level.
- Attractive: attractive means that your software should be more enjoyable and if anyone visits you software he visits again and again ....To make this you need to add different types of graphics , different styles of texts and provide the information in attractive way....
IDE, Features of visual basic
An integrated development environment (IDE) is a programming environment that has been packaged as an application program, typically consisting of a code editor, a compiler, a debugger, and a graphical user interface (GUI) builder....The BASIC programming language, for example, can be used within Microsoft Office applications, which makes it possible to write a WordBasic program within the Microsoft Word application. ...
Menu bar: This Menu Bar displays the commands that are required to build an application. The main menu items have sub menu items that can be chosen when needed. The toolbars in the menu bar provide quick access to the commonly used commands and a button in the toolbar is clicked once to carry out the action represented by it....Menu bar contains the menu like ,,,,File, Edit, View, Project, Build, Debug, Data, Format, Tools, Windows, Help....
Toolbox: The Toolbox contains a set of controls that are used to place on a Form at design time thereby creating the user interface area....Toolbox is also called heart of the visual basic because it provide a best tools for the development of application... Additional controls can be included in the toolbox by using the Components menu item on the Project menu....Some items which are included in toolbox like button. Radiobutton, checkbutton, Groupbox , panel....etc...
Solution Explorer: Solution Explorer allows you to view items and perform item management tasks in a solution or a project.It is present on the right side of the visual basic screen... It also allows you to use the Visual Studio editors to work on files outside the context of a solution or project......A single solution and its projects appear in a hierarchical display that provides updated information about the status of your solution, projects, and items. This allows you to work on several projects at the same time like creating new forms, moving from one form to another, editing forms, deleting forms..
Properties window: The Properties Window is found under the Project Explorer window. The Properties Window shows the various characteristics of selected objects. Each and every form in an application is considered an object.Each object in Visual Basic has characteristics such as color, size. . All these characteristics of an object are called its properties. Thus, a form has properties and any controls placed on it will have propeties too. All of these properties are displayed in the Properties Window....Some properties of forms are like Backcolor, background image, Form opacity, form location, size etc.....from the properties windows we can edit and give the new look to the form....
Object browser: The Object Browser allows us to browse through the various properties, events and methods that are made available to us. It is accessed by selecting Object Browser from the View menu or pressing the key F2. The left column of the Object Browser lists the objects and classes that are available in the projects that are opened and the controls that have been referenced in them...
server explorer: Server Explorer is the server management console for Visual Studio .NET. Use Server Explorer to open data connections and to log on to servers and explore their databases and system services. You can drag nodes from Server Explorer and drop them onto Visual Studio .NET designers. This creates new data components that are preconfigured to reference the item dropped. To access Server Explorer, select Server Explorer on the View menu. To make the Server Explorer window close automatically when not in use, select Auto Hide on the Window menu.
Output window: The output windows displays status message for different application in visual studio ..When you try to compile or build a solution this is where you see the result of compilation process ...This helps us to allow the the user to find the errors in the program ..To display it click View, point to other windows and select output or press Ctrl+Alt+O together from the keyboard.....message are like "The thread 0xd48 has exited with code 0 (0x0)
Debugger: The values of local variables change as a program executes. It is possible to see these changes. This is useful for when you want to make sure the values are correct. You can debug your variables in the Visual Studio integrated development environment....It has the capability of to attach to running process and monitor and debug those process...If source code for running process is available it display the code as it is being run...If the Source code is not available it shows dis assembly...Debugger also breakpoint which allows the execution to stopped temporarily at the certain position..The debugger support edit and continue i.e it allows the code to be edited when it is being run....
Menu bar: This Menu Bar displays the commands that are required to build an application. The main menu items have sub menu items that can be chosen when needed. The toolbars in the menu bar provide quick access to the commonly used commands and a button in the toolbar is clicked once to carry out the action represented by it....Menu bar contains the menu like ,,,,File, Edit, View, Project, Build, Debug, Data, Format, Tools, Windows, Help....
Toolbox: The Toolbox contains a set of controls that are used to place on a Form at design time thereby creating the user interface area....Toolbox is also called heart of the visual basic because it provide a best tools for the development of application... Additional controls can be included in the toolbox by using the Components menu item on the Project menu....Some items which are included in toolbox like button. Radiobutton, checkbutton, Groupbox , panel....etc...
Solution Explorer: Solution Explorer allows you to view items and perform item management tasks in a solution or a project.It is present on the right side of the visual basic screen... It also allows you to use the Visual Studio editors to work on files outside the context of a solution or project......A single solution and its projects appear in a hierarchical display that provides updated information about the status of your solution, projects, and items. This allows you to work on several projects at the same time like creating new forms, moving from one form to another, editing forms, deleting forms..
Properties window: The Properties Window is found under the Project Explorer window. The Properties Window shows the various characteristics of selected objects. Each and every form in an application is considered an object.Each object in Visual Basic has characteristics such as color, size. . All these characteristics of an object are called its properties. Thus, a form has properties and any controls placed on it will have propeties too. All of these properties are displayed in the Properties Window....Some properties of forms are like Backcolor, background image, Form opacity, form location, size etc.....from the properties windows we can edit and give the new look to the form....
Object browser: The Object Browser allows us to browse through the various properties, events and methods that are made available to us. It is accessed by selecting Object Browser from the View menu or pressing the key F2. The left column of the Object Browser lists the objects and classes that are available in the projects that are opened and the controls that have been referenced in them...
server explorer: Server Explorer is the server management console for Visual Studio .NET. Use Server Explorer to open data connections and to log on to servers and explore their databases and system services. You can drag nodes from Server Explorer and drop them onto Visual Studio .NET designers. This creates new data components that are preconfigured to reference the item dropped. To access Server Explorer, select Server Explorer on the View menu. To make the Server Explorer window close automatically when not in use, select Auto Hide on the Window menu.
Output window: The output windows displays status message for different application in visual studio ..When you try to compile or build a solution this is where you see the result of compilation process ...This helps us to allow the the user to find the errors in the program ..To display it click View, point to other windows and select output or press Ctrl+Alt+O together from the keyboard.....message are like "The thread 0xd48 has exited with code 0 (0x0)
Debugger: The values of local variables change as a program executes. It is possible to see these changes. This is useful for when you want to make sure the values are correct. You can debug your variables in the Visual Studio integrated development environment....It has the capability of to attach to running process and monitor and debug those process...If source code for running process is available it display the code as it is being run...If the Source code is not available it shows dis assembly...Debugger also breakpoint which allows the execution to stopped temporarily at the certain position..The debugger support edit and continue i.e it allows the code to be edited when it is being run....
Events...
Visual Basic is an event driven program. For an example, take a button on a Windows Form. When you click on the button, it is an event. Visual basic include many types of events like onmouseover, onmouseleave, etc....All function differently.... That event invokes a method and executes a part of the program.
A Scroll bar have events scroll and change. When you scroll the scroll bar, it is an event for the scroll bar. When you click on a position on the scroll bar, the value changes at one and it is another event. These different events can invoke different methods...
Give example..
A Scroll bar have events scroll and change. When you scroll the scroll bar, it is an event for the scroll bar. When you click on a position on the scroll bar, the value changes at one and it is another event. These different events can invoke different methods...
Give example..