About this chapter
This chapter provides an overview of the techniques you can use to develop Web applications with PowerBuilder.
PowerBuilder provides several tools that you can use to build Web applications. This section provides a brief overview of these tools and points to where you can find more information.
Appeon PowerServer
Appeon PowerServer is a product that deploys existing PowerBuilder client/server applications to the Web. For more information, see the PowerServer website at https://www.appeon.com.
.NET Assembly target and .NET Web Service target are considered to be obsolete. The ability to use these techniques have been retained for backward compatibility.
You may consider using the the section called “HTTPClient object” object as a replacement.
Obsolete technique
Creating Web service proxy for connecting to SOAP server will no longer be eligible for technical support. Developers who build Web service client that connects to SOAP server can choose to either continue using the feature without support, or use the section called “HTTPClient object” to call SOAP Web service. For more information, refer to this article: Call SOAP Web Service Using HTTPClient Object.
Web services are loosely defined as the use of Internet technologies to make distributed software components talk to each other without human intervention. The software components might perform such business logic as getting a stock quote, searching the inventory of a catalog on the Internet, or integrating the reservation services for an airline and a car rental agency. You can reach across the Internet and use preexisting components, instead of having to write them for your application.
A PowerBuilder application can act as a client consuming a Web service that is accessed through the Internet. Through use of SOAP and WSDL, a collection of functions published remotely as a single entity can become part of your PowerBuilder application. A Web service accepts and responds to requests sent by applications or other Web services.
Obsolete technique
Web DataWindow is not recommended and is considered to be obsolete. The ability to use this technique has been retained for backward compatibility.
An obsolete feature is no longer eligible for technical support and will no longer be enhanced, although it is still available.
The Web DataWindow is a thin-client DataWindow implementation for Web applications. It provides most of the data manipulation, presentation, and scripting capabilities of the PowerBuilder DataWindow without requiring any PowerBuilder DLLs on the client.
The Web DataWindow uses the services of several software components that can run on separate computers:
-
Web DataWindow server component running in an application or transaction server
-
Dynamic page server
-
Web server
-
Web browser
-
Database
The server component is a nonvisual user object that uses a DataStore to handle retrieval and updates and generate HTML. You can use the generic component provided with PowerBuilder or a custom component.
You can take advantage of the capabilities of the Web DataWindow by:
-
Hand coding against the Web DataWindow component
You can write server-side scripts that access the Web DataWindow component directly.
-
Writing your own HTML generator
Using a sample PBL provided with PowerBuilder as a starting point, you can create your own HTML generator that provides the methods you need for your application.
Obsolete technique
DataWindow Web Control for ActiveX is not recommended and is considered to be obsolete. An obsolete feature is no longer eligible for technical support and will no longer be enhanced, although it is still available.
The ability to use this technique has been retained for backward compatibility.
The DataWindow Web control for ActiveX is a fully interactive DataWindow control for use with Internet Explorer. It implements all the features of the PowerBuilder DataWindow except rich text.
The DataWindow Web control for ActiveX supports data retrieval with retrieval arguments and data update. You can use edit styles, display formats, and validation rules. Most of the PowerBuilder methods for manipulating the DataWindow are available. Several functions that involve file system interactions are not supported, allowing the Web ActiveX to be in the safely scriptable category of ActiveX controls.
Included with the DataWindow Web control is the DataWindow Transaction Object control for making database connections that can be shared by several DataWindow Web controls.
The Web ActiveX is provided as a CAB file, which allows the client browser to install and register the control. When the user downloads a Web page that refers to the CAB file, the browser also downloads the CAB file if necessary, unpacks it, and registers the control.
