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PowerBuilder |
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CSC 340F – Information Systems Analysis and Design |
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Assignment 4 – Research Question 7 |
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Instructor: |
Eric Harley |
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Submitted By: |
Michal Jordan-Rozwadowski |
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The Basics of PowerBuilder |
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PowerBuilder is an event-driven, object-oriented language. The programmer creates objects and then
defines the behaviour of the system in terms of the objects and the events which can occur in the
context of an object.
PowerBuilder Objects
The basic building blocks of a PowerBuilder application are objects. All programming in the PowerBuilder
environment takes place in the context of objects. These objects, their scope and their use are
represented in the following table:
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Object |
Use |
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Application |
Entry point into an application |
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Window |
Primary interface between the user and a PowerBuilder application |
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DataWindow |
Retrieves and manipulates data from a relational database or other data source |
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Menu |
List of commands or options that a user can select in the currently active window |
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Global function |
Performs general-purpose processing |
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Query |
SQL statement used repeatedly as the data source for a DataWindow object |
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Structure |
Collection of one or more related variables grouped under a single name |
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User object |
Reusable processing module or set of controls |
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Library |
Stores PowerBuilder objects, such as windows and menus |
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Project |
Packages application for distribution to users |
Associated with each object is a
of any of the above types and easily modify its attributes and behaviour.
Event-Driven Programming
The behaviour of the objects is defined in terms of events. When an event occurs in the context of
an object, this triggers a section of code, which is then run. The code which is attached to these
events is in a language developed by Sybase for PowerBuilder, called
PowerScript.