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Archive for the ‘Visual Developer’ Category

Visual Basic is the most familiar and popular programming language introduced by Microsoft which is used by software merchants, programmers and developers to produce a graphical client request interfaces. Visual Basic programmers make use of GUI to select and change already selected sections of the code written in the BASIC programming language. Visual Basic is quite easy to understand and also it is easier and faster to write the coding. At times it is used to prototype an application which would further be written in a very hard but with proficient language.

Visual Basic is basically a Windows based programming language. It is exclusive as it could execute and show graphics and it is very much easier to perform. Visual Basic flings out the opening, central and rear concept. The end part depends on the work the user performs. The end part is not the exact ending of the programming it is still just an opening. On the other hand Visual Basic has an object oriented attitude. It is called as an Event-Driven programming language, as each and every object will respond to various events of mouse like click and double click. Visual Basic is Microsoft’s entry-level programming language for Windows Operating System.

Visual Basic is derived sturdily from BASIC and it permits the RAD that is Rapid Application Development of the GUI application to retrieve the database by making use of controls like ADO, RDO, and DAO. Programs done in Visual Basic can moreover utilize the Windows Application Programming Interface. For utilizing this it necessitates external function declarations. Visual Basic is deliberated and designed inorder to make the learners understand and study it easier and use it simpler. It permits the Visual Basic Developer to generate an easy Graphical User Interface application and it also gives the maximum flexibility to the programmers.

The Visual Basic contains several tools for placing the controls in each form. There are several controls like List Boxes, Text Boxes, Radio Buttons, Timer Controls etc., while creating these controls it already holds a default value for each controls. At times it can be altered by the VB developer. Depending on the user actions or modifications in the setting the attribute values can be customized while run time providing it as a dynamic application. Visual Basic can produce an ActiveX controls, Dynamic Link Library files, EXE files. Mainly Visual Basic is used to generate Windows applications and also to interface the database systems. Visual Basic will not permit constant variables to control an array and so an additional processing is necessary to follow it.

The recent versions of Visual Studio are – in chronological order – 2005, 2008 and 2010. You can download VS Express free of charge from the Microsoft website, but this article only considers the paid-for applications. As far as we’re aware, there is virtually no difference between the free and paid-for versions at the developer level.

Reasons to Choose VS 2005 (or higher)

Visual Studio hasn’t really changed in functionality since VS 2005. All of the familiar windows haven’t changed: Solution Explorer, toolbox, etc, and the coding and development environment would look familiar to any user of VS 2008 or 2010. So if you already have a licence to use VS 2005 and don’t spend too much time developing applications, stick with VS 2005.

Reasons to Choose VS 2008 (or higher)

Notwithstanding the comments above, there are two very good reasons to upgrade to Visual Studio 2008. The first one is that it includes support for the LINQ database language and for AJAX, so if you use either of these development tools you’ll need to upgrade to at least VS 2008. The second reason to upgrade is that VS 2008 includes much better autocompletion, which makes a big difference if you spend most of your working hours coding.

Here’s how it works. Supposing you have declared a variable called myShinyVariable and you want to assign a value to it. In VS 2005 you would have to press CTRL + SPACEBAR to bring up the name of the variable in Intellisense. In VS 2008 and above, just start typing myS and the variable name will automatically appear. This feature gets addictive!

Reasons to Choose VS 2010

Although Visual Studio 2010 contains a lot of nice features for the serious developer, we don’t think the average person will benefit too much from the upgrade. The one unmissable feature is that – at last – you can now zoom in and out by holding down the CTRL key and rotating a mouse wheel.

There is one reason NOT to upgrade. In VS 2010, when you click on any variable, property, method, object or whatever, Visual Studio will highlight all instances of it throughout your code. Although this should be a good feature, we find it irritating (and will turn it off when we find out how).

Conclusion

If you’re just buying Visual Studio for the first time, it makes sense to go for the latest version; however, if you’re stuck with version 2008, you’re not missing a great deal. Visual Studio 2005 programmers should upgrade if they want to use AJAX within their websites or if they want to speed up their typing.

.NET platform does not support multiple inheritance. Do not confuse multilevel inheritance with multiple inheritance. With multiple inheritance we can have a subclass that inherits from two classes at the same time.

Let’s suppose we have an application that has a class Customers and another class Vendors. If you wanted to combine these two classes into one CustomerVendor class it would be a combination of Customers and Vendors just like the diagram below.

Please copy the following URL into your browser to view the diagram: [http://www.vbprofs.com/images/Article] Images/ThomasArt1.gif

In the above diagram we see how the CustomerVendor class inherits from both of those classes.

Multiple inheritance is complex and can be dangerous. The advantages of code re-usage prevail over complexity is up to your choice.

Multiple inheritance is not supported by VB.NET or .Net platform. Instead of multiple inheritance we can use multiple interfaces to achieve similar effect to multiple inheritance.

In VB.NET all objects have a primary or native interface, which is composed of properties, events, methods or member variables declared using Public keyword.
Objects can implement also secondary interfaces by using Implement keyword.

Sometimes it is helpful for an object to have more than one interface, allowing us to interact with the object in different ways. Inheritance allow us to create subclasses that are a specialized case of the base class.

Example

Sometimes we have a group of objects that are not the similar, but we want to handle them the same manner. We want all the objects to act as if they are the same, even though they are different.

We can have some different objects in an application, such as customer, product, invoice etc. Each object would have a default interface appropriate to each individual object, and each of them is a different class. No natural inheritance is implied between these classes.
Let’s suppose we want to print a document for each type of object. In this case we’d like to make them all act as printable object.
To accomplish this we can define a generic interface that would enable generating a printed document.
By implementing a common interface we are able to write a routine that accepts any object that implements a printed document.

To conclude, by implementing multiple interfaces in VB.NET , we can achieve a similar effect to that of multiple inheritance.