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This article will explain in detail how to implement class construction in VB.NET. The editor thinks it is very practical, so I share it with you for reference. I hope you can get something after reading this article.

VB.NET class

I have mentioned in previous articles that the emergence of VB.NET has brought about great changes in the concept and operation of classes in VB6. Now let's go into these changes for a more in-depth discussion. First of all, let's look at what classes really mean.

Suppose I brought you back to college, and now that you walk into a classroom, I ask you to explain what a class is, and you might say, "A group of students forms a class." Oh, if you answer in this way, you are really getting it straight: yes, here, group is the most important word. From the point of view of object-oriented programming, a class is a way to store data and give coordination to a set of related code. Class is the core of object-oriented programming.

The new face that .NET gives to the class

The primary significant difference between VB6 and VB.NET in the use of classes is that the latter no longer uses the Set keyword. In addition, the way classes are defined in your code has changed. These changes will not only directly affect the code you write, but also change the way you organize your source files.

Under VB6, each class must be added and defined within a single source file. This is not the case under VB.NET: classes are defined in the form of code blocks, as follows:

Public Class MyClass' writes the member code of the class here! End Class

In the face of such a revolutionary change, some people may be worried about bubbling in the corners of their mouths, while most people may not care or understand the use of code blocks to define classes. Seriously, it all depends on your taste. Some people like and want only one class to be defined in a file, while others prefer to organize their classes logically. For example, if you have a product class and a corresponding products collection class, you can put them in the same file to better organize the source file.

Construction and deconstruction of VB.NET classes

When your code creates an instance of a class, it calls a special method of the class: the constructor. Similarly, the destructor method is called when the class is corrupted. In most object-oriented languages, the above two general terms are usually used when it comes to class construction and destruction, rather than the member name of the specific coding. I prefer to use the term "structors" to refer to construction and destructions. In VB6, the specific "structors" is Class_Initialize and Class_Terminate. Under VB.NET, the Class_Initialize method is renamed to New, and Class_Terminate becomes Finalize.

According to VB6's implementation restrictions on class constructors, programmers are not allowed to add parameters to the method. However, parameter support is provided for constructor methods in VB.NET. Under VB.NET, you can now optionally add parameters to this method, or even overload it.

How can parameterized constructors flexibly create classes? For example, suppose you have an ADO Connection class. In VB6, you have to instantiate the class first, and then define the connection with the ConnectionString attribute in the code. To use VB.NET, the class's constructor is parameterized and overloaded so that you can pass a connection string to the object when the programmer instantiates it, so you don't have to worry about how to set up future connections in the code. Of course, you can do it the old-fashioned way: no arguments are passed, and the connection string is set in the code later.

This is the end of this article on "how to implement class construction in VB.NET". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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