6-15
Concepts - Serial COM When you use drop-in components in your program you will follow the
standard object-oriented programming paradigm that uses properties,
methods, and events to implement the functionality of the drop-in
component.
• Properties are the various configuration variables used by the
drop-in component. An example of a property is the
ComDeviceName setting.
• Methods are function calls used to issue commands and access
features of the drop-in component. An example of a method is
sending an Input command to the terminal.
• Events are function definitions placed in your application’s source
code. The function definitions in your source code are called Event
Handlers. The skeleton structure of the event handler’s source code
is automatically generated. The code in the Event Handler is called
("fired") by the drop-in component when a specific event occurs.
An example of an event is when a terminal returns data and the
OnTermData event is fired.
The details of how to access Properties/Methods/Events varies between
development platforms. Details of how it works in some of the most popular
platforms is illustrated in the samples included with the RF Utilities CD or
available for download from our website at:
http://www.barcodehq.com/wdterminal.exe
Properties - Serial COM
Properties are the various configuration variables used by the WDterm
control. They are directly assignable in your application (e.g.
"WDterm.ActiveTerminal = 5") and can be set in your development
environment’s object browser.
Important: Except for ActiveTerminal and Quiet, all properties require the
serial port to be "closed" before they can be changed. Use the CloseDevice
method before setting properties and then call OpenDevice to re-open the
serial port.
Note that your development environment may show more properties for the
WDterm control than are listed here. This is normal. You may ignore
properties you see that are not listed here.