دانلود Microsoft Visual Studio 1997 SP3 Enterprise + MSDN Library نرم افزار ویژوال استودیو 1997

A second target of Visual Studio is the corporate client-server application. The same basic architecture applies to both types of applications. Corporate applications tend to focus a little more on the database side of things, though, and the Visual Studio Enterprise Edition contains even more tools for creating large-scale database and transaction-processing applications.

Visual Basic is Microsoft's RAD tool for Windows programmers. Visual Basic uses a graphical, forms-based approach to application development. The typical way to write a program in Visual Basic is to create a form, drag and drop components onto the form, set properties for the form and its components, and add application-specific code to handle events. It sounds simple, but you can write some very powerful applications this way.

The great thing about Visual Basic is that it hides most of the gory details of Windows-based programming and lets you focus on your application-specific functionality. Pretty much every service you use in a Visual Basic program is provided by an ActiveX component. Once you've learned how to use one component in Visual Basic, using any other component is simply a matter of learning how its object model—its properties, methods, and events—works.
If you've used Visual Basic before, one of the first things you'll notice is that Visual Basic 5.0 has a new integrated development environment (IDE).

Visual Basic 5.0 makes ActiveX control creation incredibly easy. You can either combine existing controls into a new component or create a component from scratch. Either way, you use a special kind of object, called a UserControl, as the basis for your ActiveX control. Once you've added any constituent controls to the UserControl, you use the ActiveX Control Interface Wizard to specify which properties, methods, and events your composite control will expose to clients. You can create property pages for your control using the PropertyPage Wizard.

The major limitation to the Visual Basic 5.0 control creation features is that the controls you create are single-threaded. In addition, I didn't see any support for windowless controls. But if you can live with these restrictions, Visual Basic now provides a great way to create powerful, lightweight controls. If you'd like to know more, take a look at Guy and Henry Eddon's articles in the February and March 1997 issues of MSJ.

Using another special object called a UserDocument, you can create ActiveX Documents as easily as you design a form. When you create an ActiveX Document in Visual Basic, you add controls to a UserDocument instead of adding them to a Form. In fact, Visual Basic provides a wizard for converting ordinary apps into ActiveX Documents: the ActiveX Document Migration Wizard. This wizard converts the project type to ActiveX Document DLL or EXE and adds a UserDocument to the project. It then copies a form's properties, controls, and the code behind the controls to the UserDocument object, and migrates form event handlers to the UserDocument equivalents.

ActiveX Documents created with Visual Basic are a little different than other ActiveX Documents you may have encountered. Visual Basic ActiveX Documents are roughly equivalent to Visual Basic forms that can only be hosted in ActiveX Document containers—you can't run them as standalone applications. ActiveX Documents are typically activated by accessing a file. When you create an ActiveX Document project in Visual Basic, it generates a file with a .VDP extension. This is a structured storage file containing the CLSID of the ActiveX Document that should be launched, and any persistent properties exposed by the document. However, the emphasis in Visual Basic seems to be related more to making a Visual Basic application run within a document container such as Internet Explorer than on the "persisted" data (contrast this with Word, where the emphasis is clearly on the persistent document).

Once you've created a component, you'll need to distribute it to your clients. Visual Basic provides a Setup Wizard to help you with all the packaging issues associated with distributing applications and components. The wizard has been enhanced in version 5.0 to support distribution via the Internet. It also supports installation of remote server components using either DCOM or RA.