Scripting Overview

ActiveX scripting is a key technology in the Data Master 2003. This software utilizes scripts to implement its standard functionality as well as to add new user-defined features. In fact, a simple mathematical operation or data acquisition application requires several dozens of lines of easy-to-understand VB code and may be created in hours even if you are not a professional programmer. At once, this technology has virtually no restrictions. With additional ActiveX controls accessed from scripts your application may be as complex as you need. DM2003 software supports standard language engines preinstalled with any copy of Windows operating system or Internet Explorer browser.

Features based on scripting technology:

• Scripter.DLL - default Action Provider that implements almost all standard features of DM2003 application. Generally speaking, each menu item or toolbar button in DM2003 is linked to the invisible Action object. This object has several attributes - ID, Caption, Hint and two methods - Execute and Update. Execute method is called when user activates appropriate control (e.g. selects menu item or clicks the button). Update method is called periodically (in the application's message processing cycle) to set correct item state, for example, to enable/disable linked controls when operation is not possible. The scripter.dll unit maintains extendable list of action objects, by associating several specially named language elements (variable and function definitions) with every action.
  
  At DM2003 startup, scripter.dll unit compiles master script file (with standard actions definitions) and installed user scripts and builds action list. Users may easily add new actions: just create and install new user script file and action object (s) as described in the example below (both master script and user scripts must be written in the same language). If you need to change standard actions behavior, edit master script file.
  
  Keep in mind that scripter.dll unit supports application event handlers and additionally compiles all definitions from both DM and DMForms type libraries, so that you can use symbolic constant names in your scripts. Besides, you can use its Connectable Objects feature - namely, create specially defined ActiveX objects that can be bound to the event handlers in your script code (ones created by CreateObject() function can't). DMInternalApplication object is available through predefined Server variable.
  
  
• Browser Window and HTML Dialogs - are containers for user-defined HTML with embedded scripts. HTML used in the DM2003 to define customizable user interface for various operations implemented by the script code. Unlike usual web pages on the internet sites, you open HTML documents for DM2003 into specialized instances of MSIE (TWebBrowser control) that have full access to the DM2003 object model.
  
  For Browser Window, reference to the DMInternalApplication object is available via window.external property. Events are also supported, so that your applications can be more interactive, for example, you may process plot point clicks and so on.
  
  HTML Dialog boxes may be displayed using IDMApplication2.ShowDialog method. Scripts in dialog box HTML should access DMInternalApplication object using window.external.Server property. You also may use window.external.Close method to close dialog box programmatically (typically in OkButton_onclick event handler) and window.external.Arguments property to obtain read/write access to the dialog box arguments. Modeless dialog boxes implement additional property - window.external.IsVisible that allows you to hide or show dialog window. For modeless dialog boxes, ShowDialog method returns reference to the TWebBrowser object, thus you have full access to the contents of the HTML document. Events are also supported.
  
  In addition, you may use any ActiveX controls to add custom functionality to your HTML application. This may be specialized user interface controls, hardware drivers or any other API wrapped into ActiveX/COM interface. A number of useful ActiveX controls (dmforms.ocx unit) installed with the DM2003 software package.
  
  
• Script Editor - allows you to edit, compile and run scripts. Use it to debug scripts or automate single use tasks, when you don't wish to make special menu item or toolbar button. In addition, you may explore DM2003 object model and dispatch objects.
  
  Notice that you also may use professional script debuggers (free stand-alone Microsoft Script Debugger or Microsoft Script Editor bundled with the Microsoft Office and Microsoft Visual Studio) to edit and debug scripts and HTML documents running into DM2003 process. This is a feature of the TWebBrowser control and script engines.
  
  

VBScript or JavaScript?

Frankly speaking, this paragraph should be titled "Why VBScript?". Although two standard language engines, namely vbscript.dll and jscript.dll are installed on any Windows system, in fact, DM2003 uses VBScript as a primary scripting language. There's a nice article on the MSDN that discusses advantages and shortcomings of every language. In particular for DM2003, following VBScript features tip the scales:

• More straightforward syntax, very popular between engineers and scientists
• More powerful (error handling, "ByRef" (output) parameters, "true" binary arrays)
• More suitable for arbitrary objects (JavaScript is targeted at the web browsers)

1. Use Help|Wizards|Action Wizard in the Script Editor to create following code:

'//////// MyTestAction Action /////////

const MyTestAction_Caption="My Test Action"
const MyTestAction_Hint="Displays active document caption"

sub MyTestAction_OnExecute
  '<put sub body here>
  MsgBox Server.ActiveDocument.WindowCaption
end sub

function MyTestAction_OnUpdate
  MyTestAction_OnUpdate=dmuaVisible '<-modify this code
  if Server.DocumentCount>0 then
    MyTestAction_OnUpdate=dmuaVisible+dmuaEnabled
  end if
end function

2. Now save script to the disk file (or place it somewhere on the web) and bring up New Action dialog box as described in the help on Customize Menu and Toolbars dialog box.

3. Select "HTML/Scripting action provider" and click "Configure selected provider" button. On the "User Files" tab, click "Add" button and select script file. Click "OK" to save changes.

4. Restart DM2003 and bring up New Action dialog box again. Select "HTML/Scripting action provider" and select MYTESTACTION action from the list of Action IDs. You may also set image and category. Click "OK" to add new action.

5. Drag "My Test Action" from the list of actions ("Actions" tab) onto the toolbar or menu and close dialog.

That's all job! If you made no errors, new menu item (or toolbar button) will display caption of active data window or will be disabled if there's no data windows.

What to do if there's errors in the script file and you see script compilation error message at startup? You can't remove this file until you load into DM2003! Just rename or move the file - if DM2003 couldn't find it, it will be ignored.