These pages were the activescripting newsgroup FAQ. They were collected by Mark Baker, and originally were hosted on his site. His website is down since several years, I tried to contact him but couldn't. I hope everything is fine for you Mark.

This FAQ has been invaluable resources when working on FScript (a FARR plugin ). It's a little bit old technology but it can do great stuff still.

I couldn't get back some of the pages from google cache or from web archive. If someone has them, I'll be happy to add them.

Introduction

• Copyright
• Scripting FAQ Info and Credits
• Where to go for ActiveX Scripting Information
  • Microsoft
  • MSDN
  • Knowledge Bases
  • Articles/Columns
  • Newsgroups
  • Web sites
  • Mailing Lists
  • Books & Magazines
• Using ActiveX Scripting

Getting Started

• What is the Active Scripting Interface?
• Are there any samples available from Microsoft (or others) that show how to work with ActiveX Scripting?
• Does Microsoft have a FAQ for Active Scripting?

Hosting – General

• What is the minimum I have to support from the Active Scripting interfaces in order to be a host?
• What is the difference between a "dumb" host and a "smart" host?
• Why is the documentation on the Microsoft web site and the Microsoft Developer Network Library not up-to-date for all of the available Active Scripting interfaces?
• Where can I get the type library information for the Active Scripting interfaces?
• What is the definition of the error codes reported by the engine?
• How can I determine what Active Scripting engines are installed on my machine?

In the .NET World

• Has anyone heard anything about the script engines future in light of .NET?
• Does this mean the end of being able to implement an Active Script Host and a custom script engine in a .NET world?

Hosting – Running Scripts

• How do I execute a script in a given language?
• How can I call a specific function or subroutine within my script?
• How can I determine the correct scripting engine to create from a script’s text?
• What is the easiest way to re-execute a script?
• When I’m done with the scripting engine, how should I release the engine?
• How do I trap runtime errors in my script?
• Why does setting the boolean variable "callOnScriptErrorWhenContinuing" in IActiveScriptSiteDebug::OnScriptErrorDebug() not call IActiveScriptSite::OnScriptError?
• How do I signal an error from my host that can be trapped by my script?
• How do I handle script errors without using the script debugger?
• How do I disable the script debugger for my scripts?
• How do I trap syntax errors in a script within my host?
• If the engine reports an error in a script, how do I know where the error is located?
• If the engine reports an error in a script, how do I know what kind of error it found?
• How do I know when a script is finished executing?
• If I call methods on the scripting engine from a thread other than the one I used to create the engine, I get the HRESULT E_UNEXPECTED. What do I need to do to be able to call the engine from any thread (or multiple threads)?
• In the IActiveScriptParse->ParseScriptText interface/method, what is the definition of the "pszItemName" parameter?
• In the IActiveScriptParse->AddScriptlet method what is the difference between the pstrDefaultName, pstrItemName and pstrSubItemName arguments?
• Can the IActiveScriptParse->AddScriptlet method be used to add general functions to a script that are callable by the script passed to the engine via IActiveScriptParse->ParseScriptText?
• Is there an example of a host using IActiveScriptParse->AddScriptlet?
• Why does my app crash inside OLEAUT32.DLL after I call IActiveScript::InterruptScriptThread?
• What is the state of the script engine after calling IActiveScript::InterruptScriptThread?
• What are the semantics of IActiveScript::Clone?
• How can I add 2 or more sets of script text to the engine via IActiveScript->ParseScriptText and get back an Idispatch pointer for each script?
• What is error code 0x80020101?
• How can I run a script using the security credentials of the client?
• I'm getting script error 0x8000FFFF when trying to move to the CONNECTED state after my script was terminated by InterruptScriptThread. What am I doing wrong?
• Why would I get a 'Catastrophic Failure' HRESULT back from from either ParseScriptText or from SetScriptState?
• Why does the documentation state that I can call IActiveScript::SetScriptState from a secondary thread, but I get a ‘Catastrophic Failure’ HRESULT back when I try to call it?
• Why would I get a ‘Catastrophic Failure’ HRESULT (0x8000FFFF) back from IActiveScript::GetScriptDispatch?
• How can I implement "modules" functionality in my host similar to what the Microsoft Script Control offers?
• What is the expected behavior of the flags that can be passed to IActiveScript::InterruptScriptThread?
• How can I programatically access the global variables & functions in a script?
• Why does IActiveScriptError::GetSourceLineText return E_FAIL when called after a runtime error occurs?
• Are there any special flags I need to pass to IActiveScript::AddNamedItem() in order to parse a script in a named context?
• Is there any way to save parsed code into a binary format to eleviate having to re-parse the code at a later time?
• How can I pause and then resume the execution of a script from where it was paused?
• Which IPersistXXX interface should I use to load source code (script) into an engine?
• What would be the proper way to terminate a script from an automation object method that was added using AddNamedItem? I've tried InterruptScriptThread, then SetScriptState(SCRIPTSTATE_DISCONNECTED), doing this this fires an error on the next line of code following the method that quits the script. Also tried calling OnScriptTerminate directly, somewhere in this mixture has to be a clean way to exit.
• How can I support multiple scripting languages such that scripts written in one language can call scripts written in another language (ie. VBScript calls Jscript, etc)?
• Can the Dispatch pointer retrieved with GetScriptDispatch() be passed between threads?
• How can I safely use a script interface (like an IDispatch pointer) in a secondary thread if that thread doesn't own the interface?
• What is the best way to reset the scripting engine between uses?
• What is the purpose of the IActiveScriptParseProcedure interface?
• What is the purpose of the IActiveScriptStats interface and methods?
• Is there a complete description of the multithreading support within Active Scripting?
• Why would IActiveScript::InterruptScriptThread return E_INVALIDARG if I know the parameters passed to InterruptScriptThread are valid?
• Why does IActiveScript::InterruptScriptThread not terminate a running script immediately when I'm trying to kill the script engine?
• How can I save/restore the values of script variables between runs?
• What is the difference between the IActiveScript interface and the IScriptControl interface?
• Is there a way I can access the parameters of an event within a script added via IActiveScriptParse::AddScriptlet?
• What are the correct HRESULT values to return when using the interface IActiveScriptSiteInterruptPoll?

Hosting – Debugger

• How can I launch the debugger and have it stop on a breakpoint in my script similar to what Internet Explorer does?
• I want to implement support for Active Script Debugging. Where do I find the header files for these interfaces?
• What’s the minimum I need to do to add Active Script Debugging support to my host?
• How can I get the runtime value of a variable used in a script using an Active Scripting interface?
• How can I get a list of the stack frames when the debugger stops at a breakpoint?
• How can I evaluate a "watchpoint" string that the user enters into my application?
• How can I execute some code while stopped at a breakpoint and have it update the script "on-the-fly"? This is similar to an "immediate" code window in Visual InterDev.
• How can I set a breakpoint within a script?
• How can I remove a breakpoint within a script?
• How can I remove all breakpoints within a script?
• How can I implement single-stepping (such as step over, step into, etc) in the debugger?
• How can I get a list of the variables within a stack frame?
• Why does the IEnumDebugPropertyInfo::Next() method crash if I attempt to iterate blindly?
• How can I send information from my object to the debugger such as the Microsoft Script Debugger?
• What is the best way to find the current execution point when the debugger has stopped at a breakpoint?
• Who implements the IDebugSessionProvider interface?
• Who calls IDebugSessionProvider::StartDebugSession?
• Who calls IApplicationDebuggerUI::BringDocumentToTop and IApplicationDebuggerUI::BringDocumentContextToTop?
• When the debugger breaks at a breakpoint it calls IApplicationDebugger::onHandleBreakPoint. Why does my app hang when I try to call IDebugApplication::ResumeFromBreakPoint later?
• How I can force the registered debugger (such as the Microsoft Script Debugger) to launch when debugging?
• How can I have the script engine ignore the registered debugger (such as the Microsoft Script Debugger) and use my implementation of the debugging interfaces?
• Why do I get the error message "Source code is not available for the current statement" from the debugger?
• Why do breakpoints appear on different lines than what I specify?
• Why would I receive an E_UNEXPECTED error code from the method IActiveScriptDebug::EnumCodeContextsOfPosition?
• How can I implement a "set next statement" feature in a debugger?
• Why does my application crash if my host supports the debugging interfaces, but the script debugger is not installed?
• Why does the call to IActiveScriptDebug::EnumCodeContextsOfPosition() crash if there are no executable lines of text in a script?
• What initialization do I need to do on a Clone'd engine with a host that supports debugging?
• How can I send text to the Output window of the Debugger from within a script?

Hosting – Objects & Events

• What interfaces do my COM objects need to support so the script engine can connect to fire events?
• What is the best way to add event handling code to the script engine?
• What is the best way to design my objects so that they will be compatible with Active Scripting?
• I know JScript has dynamic object support whereby I can add methods and properties "on-the-fly" in my script. How can I add support for this in my objects?
• Can I use my own interface design to sink events from my objects, or do I need to use the IConnectionPoint interface?
• After adding an Automation object to the script engine’s namespace, how do I respond to its events?
• Why would IDispatch->Invoke get called with an ID of zero for an automation object in a script?
• Can an automation object’s methods use types other than VARIANT’s?
• Why would further calls to automation objects fail after calling IActiveScript->Clone?
• Where can I find information on the IDispatchEx interface?
• Where can I find more information regarding the IProvideMultipleClassInfo interface?
• My automation objects change dynamically between invocations of a script. How can I ensure that GetItemInfo is called by the ScriptEngine such that changes in any of the objects can be taken account of by me by passing back the correct IUnknown and ITypeInfo pointers from GetItemInfo?
• Can I pass simple data types like integers or strings to a script without creating an automation object to contain them?
• How can I check the version of the TLB (type library) of an object within a script?
• How can I expose arrays of values within my object to a script?
• When the script engine calls IActiveScriptSite::GetItemInfo() with the flag SCRIPTINFO_ITYPEINFO, how can I return the proper type library information for the object?
• Will the script engine call my object’s IDispatch::GetIDsOfNames() method more than once?
• How can I parent a window or dialog (that I create from within my object) to my application rather than the desktop?
• How can I sink events for objects that are created at runtime within my script (ie using VBScript’s CreateObject() function)?
• When I use On Error Resume Next in a script, any run-time error does not generate a call to either OnScriptErrorDebug or OnScriptError. We seem to go right to OnLeaveScript. Is this the expected behavior ?
• Where can I get more information on writing a collection object that can be accessible from VBScript?
• When does the IActiveScriptSite::GetItemInfo method get called by the engine?
• I want to expose my top-level object’s properties and methods without having to specify the object’s name in a script. How can I do this?
• What’s a fast way to fire events from code to a script?
• I’ve created a host and an object, but the host won’t sink any events. What am I doing wrong?
• Can a script detect when the method IActiveScript::InterruptScriptThread is called by a host?
• How do I add constants such that they are usable from within my scripts?
• How can I remove a "named item" from the engine (after previously calling IActiveScript::AddNamedItem) without using Clone?
• What is the correct way to access the automation data types such as Array, Date, etc from a host?
• Why would I receive the message "Access Denied" after putting up a MessageBox within my code after being called by a script?
• What are the differences between JScript and VBScript in the support of the IDispatchEx interface?
• How do I return error codes from an object to a script?
• How can I disable MsgBoxes from being displayed for my objects?
• Does the script engine support reentrant calls to object methods?
• How can I return more than 1 value from a object method in VBScript & JScript?
• How do I get all the global constants defined in a script?
• Do I need to implement a function in my host to allow the script engine to instantiate my automation object?
• In the IDispatchEx::InvokeEx method, what is the purpose of the DISPID_THIS and DISPATCH_CONSTRUCT parameter values?
• If I have a dual event interface, why does my application crash if I attempt to call methods on the custom interface portion?
• How can I pass a parameter into a script so that it can be used in any function in the script (like a global variable)?
• If I want to use the IDispatch interface I get from calling IActiveScript::GetScriptDispatch, can I safely cache it, or do I have to call GetScriptDispatch everytime?

Hosting – Microsoft Script Control

• Why would you want to use the Microsoft Script Control vs using the native script engine interfaces (ie IActiveScript, etc)?
• I used the MFC wizard to generate a COleDispatchDriver wrapper class around the the Script Control but it didn't generate the Run method?
• Should I use the Script Control or should I write my own Script Host using the scripting interfaces?
• How do I programmatically disable/enable the debugger when using the Microsoft Script Control?
• Is there a way to programmatically interrupt a script that is running inside the Microsoft Script Control?
• Can I re-distribute the Microsoft Script Control with my application?
• Does the OS or service packs install the Microsoft Script Control?
• Does Microsoft have a FAQ about the Microsoft Script Control?
• How do I implement a timeout mechanism similar to the Microsoft Script Control so that if a script takes too long to run I can abort it?
• How can I call a VBScript function and pass it parameters using the Microsoft Script Control?
• Why does Delphi not release script objects properly after calling Run?
• Why won’t the Script Control handle any of the events I’ve written?
• Is there a way to delete a variable from a workspace without having to use the Reset() method?
• Why would I be getting the error E_FAIL from the method AddObject() on the Script Control?
• Does calling the Reset() method in the Script Control release object references that where added with the AddObject() method?

Hosting – Miscellaneous

• How can I implement an "include" file feature so that one script can "include" another?
• I’ve run into some problems and I’m not sure whether it’s my script, or my host. Is there another host application I can try?
• What is the Microsoft Windows Scripting Host?
• Can I get a copy of the source code for the Microsoft Windows Scripting Host?
• Is there a way to access the parser of a script engine from within a script host?
• Is the scripting runtime installed with a minimal install of IE4?
• Can I re-distribute the Microsoft dll’s needed for script debugging?
• Can I re-distribute the Microsoft Script Debugger?
• Can I redistribute the Microsoft Script Debugger setup program to allow for automated download of the debugger from the Microsoft web site?
• Where can I find information on supporting Active Scripting hosting from Visual Basic?
• Where can I find information on supporting Active Scripting hosting from Delphi?
• Why does Internet Explorer crash after a JScript or VBScript function recurses more than 15 levels?
• Are there any edit-control replacements on the market that offer syntax coloring, Intellisense-like lookups, etc?
• Can an Active control function as a scripting host (or debugger)?
• When should I use SysAllocString (L"Hello, world") instead of writing L"Hello, world" in my source code?
• Is there a version of Active Scripting available on the Linux platform?
• Is there a way to evaluate a VBScript or JScript expression programmatically and get a result back?

Language Engines - General

• What scripting languages are available for Active Scripting?
• How should I decide which scripting language(s) to support in my application?
• How should I acknowledge use of the Microsoft VBScript and/or JScript scripting engines in my application?
• How do I find the CLSID for VBScript or JScript? How about a non-Microsoft engine?
• How do I find the category ID’s (CATID’s) of VBScript or JScript?
• Where can I find information or samples on writing a script engine?
• Why did the debugging behavior change between v5.0 and v5.1 of the Microsoft language engines?
• Why does IDebugApplication::CauseBreak not work the same way with v5.1 of the Microsoft engines as it did with v5.0?
• What is the recommended way to determine which script engine to use for a given file extension?
• I've created a new scripting engine. How should I go about registering it so that I can use it from Windows Scripting Host, or any other host?

Language Engines - VBScript

• What is VBScript?
• Does Microsoft have a FAQ document for VBScript?
• Why don’t the VBScript functions (such as MsgBox) work properly from within my script?
• If I wish to get a result and an additional parameter by reference from VBScript to a VC++ COM object, does the additional parameter have to be VARIANT?
• Why do I get error code 0x800A000D (Type mismatch: Ubound) from VBScript?
• What is the correct way to pass parameters ByRef in VBScript?
• Why does putting the statement "STOP" in my VBScript code not launch the debugger when it gets to that point in the code?
• Why does the VBScript engine execute a script immediately if IActiveScriptParse::ParseScriptText() is called with the script added to a global context, but not executed immediately if the script is added to a named context?
• If I use the On Error Resume Next statement in a script to trap runtime errors, how can I determine what errors have occurred later?
• Can I redistribute the VBScript help file along with the VBScript binaries?

Language Engines - JScript

• Does Microsoft have a FAQ document for JScript?
• I’m trying to decide between JScript & VBScript. Which one should I go with?
• Why can’t I use the JScript function "alert()" in my script?
• How can I get JScript to ignore event handlers for objects that don’t yet exist in my script (because they are added at runtime), but activate them once the objects do exist?
• Can I use SAFEARRAY’s with JScript?
• How can I access JScript Array’s within my script host that were created in a script?
• How can I write to a JScript Array from within my script host that was created in a script?
• Why do I have to call IActiveScript::AddScriptlet to connect an object to JScript event handling code, but not for VBScript?

Language Engines – PerlScript

• What is PerlScript?
• What does Microsoft think of using PerlScript vs one of the Microsoft scripting languages such as VBScript?
• Where can I get a copy of PerlScript?
• Has anyone run into any issues with the ActiveState ActivePerl implementation?
• Why would I get an E_UNEXPECTED error from IActiveScriptParse::ParseScriptText() in PerlScript?
• Does the PerlScript engine support named contexts?
• How can I call a VBScript scriptlet from a PerlScript scriptlet?

Language Engines – PythonScript

• Where can I get a copy of PythonScript?
• Has anyone run into any issues with the Python implementation?
• Are there any licensing issues with Python?

Language Engines – TclScript

• Where can I get a copy of Tcl Script?

Language Engines – HaskellScript

• Where can I get a copy of Haskell Script?

Language Engines – RubyScript

• Where can I get a copy of Ruby Script?

Language Engines – LuaScript

• Where can I get a copy of Lua Script?

Log

• New Entries
• Changed Entries
• History

Copyright © 1999-2004  Mark M. Baker