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This article mainly shows you "what are the main differences between VB and VB.NET". The content is simple and clear. I hope it can help you solve your doubts. Let me lead you to study and learn this article "what are the main differences between VB and VB.NET".

The main differences between VB and VB.NET:

Although VB.NET is the successor to VB 6.0, it seems to me that VB.NET retains the original trace of VB in addition to syntax, because the two are almost similar or the same above 90%. But in many other ways, VB.NET is very different from VB. It may be these differences that make VB.NET more powerful and dynamic, but it also makes it difficult for VB programmers to transform into VB.NET programmers. Because VB.NET has put forward many new functions, concepts and viewpoints, mastering VB.NET requires not only mastering grammar, but also understanding and using these new functions, concepts and viewpoints. Of course, you also need to master the .net framework and understand CLR (Common Language Runtime, universal language continuous tense). Let's briefly talk about the differences between the two in terms of data access, Web development, and component creation:

1. Data access:

The main differences are as follows: data access technology, specific implementation methods of data access and data binding.

In terms of data access technology, VB 6.0implements database access through ADO (Active X Data Object, Active X data object). At the same time, in order to ensure the compatibility with earlier versions, two data access technologies, RDO (remote data object) and DAO (data access object), are also provided. In VB.NET, ADO.NET is used to access the database. ADO.NET is part of the .NET Framework, and its corresponding class library is a true subset of .net FramWork SDK. There are many differences in concept, function, and implementation between ADO and ADO.NET. Due to the limitation of space, we will not introduce them one by one here. In fact, you can also use ADO to access the database in VB.NET, but ADO appears as a COM component in VB.NET and can only be used in VB.NET by adding references. The process of adding a reference is actually interoperable with COM components. After interoperability, COM components are no longer COM components in the previous sense, but have been transformed into .net class libraries that can be directly used by VB.NET.

In terms of the specific implementation methods of data access, there are mainly two methods to realize data access by VB 6.0. one is that in the program design stage, the data source can be bound to ADODC controls or use the data environment, and the other is that at run time, you can create recordset RecordSet objects and exchange data with recordset objects. Similarly, there are two main methods to realize data access in VB.NET: one is to create and configure the data adapter DataAdapter and generate the data set DataSet; in the program design stage, and the other is to dynamically create and configure the data adapter and create and generate the data set in operation.

On Data Bind, data binding is implemented in VB 6.0by setting the following properties of the control: DataChanged, DataField, DataFormat, DataMember and DataSource. Typically, you bind the display properties of the control to the corresponding fields in the data source. In VB.NET, data binding can be used much more widely, and any property of any control can be bound to any structure that contains data in VB.NET.

2. Web development:

VB uses Active Server Page (ASP for short) to create applications in Web. In ASP, writing Web pages is not a pure VB language, but a VB scripting language-VBScript. In VB.NET, ASP.NET technology is used to write Web pages. What is used in ASP.NET is no longer a scripting language, but a real programming language, in which VB.NET can be used. Friends who have developed ASP pages know that although writing ASP pages faces low requirements of development tools, because they are process-oriented, the slightly more complex ASP code appears disorganized, which brings trouble to program design, debugging and modification. VB.NET is based on a new framework, and VB.NET fully supports Web programming. With ASP.NET 's Web application, XML Web services and other functions based on Web, the development of Web pages by VB.NET is very similar to the development of Windows programming, and the code of Web pages is not organized.

3. Component creation:

When writing an application using VB and VB.NET, although you can add components to the application by selecting components from the toolbox and dragging them in, the implementation mechanisms of the two are fundamentally different. In VB 6.0, the components created in the application are all COM components, that is, ActiveX controls, DLL of type ActiveX and EXE of type ActiveX can be used in COM applications. In VB.NET, the components dragged into the form are based on inheritance and inherit from the corresponding classes in the SDK provided by the .net framework. After instantiation, the components are added to the design form by adding functionality. These procedures can be found in the source code of VB.NET. Every component used in VB.NET is derived from the Component or Control base class.

Of course, there are still many differences between VB and VB.NET, such as: VB 6.0only provides single-threaded mode, but does not support multithreading. In VB.NET, multithreading is fully supported. In addition, new functions such as structured exception handling are added to VB.NET. So for those VB programmers, the transition from VB programmers to VB.NET is extremely necessary.

These are all the contents of this article entitled "what are the main differences between VB and VB.NET". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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