HOWTO: Call Run() Method of the Microsoft Script Control in C++

• Microsoft Visual C++, 32-bit Editions, version 6.0
• Microsoft JScript, version 5.0
• Microsoft Visual Basic, Scripting Edition, version 5.0

SUMMARY

This article demonstrates how to use the Microsoft Script control to call functions or subroutines defined in JavaScript or VBScript.

MORE INFORMATION

The Script control has four methods. One of them is Run(), which runs a subroutine or a function. Before you call this method, specify the language of the script, set AllowUI, and add the following script to the script control:

//---------------------- Begin ---------------------------

#include <stdio.h>
#import "C:\winnt\system32\msscript.ocx"  // msscript.ocx 
using namespace MSScriptControl;

int main(void)
{
	HRESULT hr = CoInitialize(NULL);

	IScriptControlPtr pScriptControl(__uuidof(ScriptControl));

	// Create a VARIANT array of VARIANTs which hold BSTRs
	LPSAFEARRAY psa;
	SAFEARRAYBOUND rgsabound[]  = { 3, 0 }; // 3 elements, 0-based
	int i;

	psa = SafeArrayCreate(VT_VARIANT, 1, rgsabound);
	if (!psa)
	{
		return E_OUTOFMEMORY;
	}

	VARIANT vFlavors[3];
	for (i = 0; i < 3; i++)
	{
		VariantInit(&vFlavors[i]);
		V_VT(&vFlavors[i]) = VT_BSTR;
	}

	V_BSTR(&vFlavors[0]) = SysAllocString(OLESTR("Vanilla"));
	V_BSTR(&vFlavors[1]) = SysAllocString(OLESTR("Chocolate"));
	V_BSTR(&vFlavors[2]) = SysAllocString(OLESTR("Espresso Chip"));

	long lZero = 0;
	long lOne = 1;
	long lTwo = 2;

	// Put Elements to the SafeArray:
	hr = SafeArrayPutElement(psa, &lZero,&vFlavors[0]);
	hr = SafeArrayPutElement(psa, &lOne,&vFlavors[1]);
	hr = SafeArrayPutElement(psa, &lTwo,&vFlavors[2]);

	// Free Elements from the SafeArray:
	for(i=0;i<3;i++)
	{
		SysFreeString(vFlavors[i].bstrVal);
	}

	// Set up Script control properties
	pScriptControl->Language = "JScript";
	pScriptControl->AllowUI = TRUE;
	pScriptControl->AddCode(
		"function MyStringFunction(Argu1,Argu2,Argu3)\ 
		{  return \"hi there\" ;}" );

	//  Call MyStringFunction with the two args:
	_variant_t outpar = pScriptControl->Run("MyStringFunction", &psa);
	

	// Convert VARIANT to C string:
	_bstr_t bstrReturn = (_bstr_t)outpar;
	char *pResult = (char *)bstrReturn;


	// Print the result out:
	printf("func=%s\n",pResult);
	
	//  Clean up:
	SafeArrayDestroy(psa);

	CoUninitialize();
	return(0);
}

// --------------- End ----------------------- 

REFERENCES

Information on the Script Control can be found at the MSDN Scripting Site.

Additional information can be found in the following articles in the Microsoft Knowledge Base:

Q184977 FIX: ScriptControl Reports Invalid Language for VBScript in MFC

Q165967 PRB: Script Error Occurs When Referencing Non-variant Array

Additional query words: SafeArray Scriptcontrol Run

Keywords          : kbAutomation kbJScript kbScript kbVBp600 kbVC600 
Version           : WINDOWS:5.0; winnt:6.0
Platform          : WINDOWS winnt 
Issue type        : kbhowto 

Last Reviewed: June 4, 1999