Technical Reference Manual - InduSoft

Screens and Graphics
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[UsedControln]
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The CLSID and Version settings are required for each ActiveX control, and they must match the
ID and version of the actual control file(s) to which Codebase links. This allows a runtime station
to check the control against those that are already registered. If the settings do not match, then the
runtime station may unnecessarily download the same control again.
If you don't know the CLSID and Version settings for an ActiveX control, you can find them
in the registry key of an already installed and registered control. Search for the control file in
HKEY_CLASSES_ROOT\CSLID in the Windows Registry.
Also, the URL for the Codebase setting can be either absolute or relative to the Web server's "home"
directory. For example:
Codebase=http://server_address/AddOns/IndDateTimePick.ocx
…or…
Codebase=AddOns/IndDateTimePick.ocx
Finally, the Regfile settings are required only if Codebase links to a .CAB file. If it does, then
use one or more Regfile settings to name the specific files within the .CAB file that must be
downloaded and registered.
ActiveX controls are components designed according to a standard. Because InduSoft Web Studio is an
ActiveX container, you can configure and run ActiveX controls in the screens created with IWS. ActiveX
controls can provide the following interfaces:
• Properties: Variables whose values can be read and/or written for your project (e.g., Object Color, FileName,
URL, and so forth)
• Methods: Functions from the ActiveX object that can be triggered by your project (e.g., open a dialog,
execute a calculation, and so forth)
• Events: Internal messages that can trigger the execution of expressions in your project (e.g., Mouse_Click,
Download_Completed, and so forth)
The name of the properties, methods and events supported by each ActiveX depends on its own
implementation.
There are two different ways to interface your project with the ActiveX control:
• By using the ActiveX functions XGet(), XSet() and XRun()
OR
• By using the Object Properties window to configure the object
Double-click on the ActiveX Control to open the Object Properties dialog.
Object Properties: ActiveX Control
The Object Properties window displays the name of the ActiveX control. Generally, each ActiveX control is
either a *.dll or a *.ocx file registered in your local computer. You must assign a name (alias) to the ActiveX
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InduSoft Web Studio