Nonvisual extension example
To illustrate the principles involved in building and using an extension, this chapter starts with a sample application that uses a PowerBuilder extension to perform a simple arithmetic operation. Ordinarily, this is not a task that needs PBNI, but it is used here to make the basic process clear. The rest of this chapter describes building extensions in more detail.
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PowerBuilder extensions are DLL files but typically use the file extension .pbx instead of .dll. Your extension is compiled into a PBX file by default if you use the wizard described in Appendix A, "Using the Visual Studio Wizards"
For more realistic examples, see the PowerBuilder CodeXchange Web site .
The following sample application has two main steps: