What is the difference between new ActiveXObject() and WScript.CreateObject()?

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According to the Microsoft documentation, one can create instances of the COM objects using both the ActiveXObject() and the WScript.CreateObject() functions. It seems like the lines

var objXL = new ActiveXObject("Excel.Application");

and

var objXL = WScript.CreateObject("Excel.Application");

are identical. Is this a true assumption? and if not what is the difference? Examples to show the difference would be highly appreciated.

P.S. The post this has been flagged as a duplicate to is about the difference between VBScript's CreateObject() method and JScript's WScript.CreateObject(). It answers mention the JScript's ActiveXObject() constructor with no further elaborations.

jscript wsh activex
1 Answers

Are they the same?

The short the answer is Yes they are the same (in the sense they perform the same job of instantiating an automation object).

Basically unlike VBScript which has the global function CreateObject() there is no such equivalent in JScript which was based on ECMAScript 3rd Edition. So, Microsoft added its own extension ActiveXObject which does the same job as CreateObject.

Both languages can be hosted in the Windows Scripting Host which gives them access to WScript.CreateObject() which is another method that does exactly the same function but only in the context of the WScript object that is only available through the Windows Scripting Host.

Following up

There has been some debate about whether they are the same, I still stand by my original answer they are the same. However, I will concede that I was comparing VBScript CreateObject() and JScript new ActiveXObject() not Wscript.CreateObject() (which is slightly different).

Let's be clear though, all these functions and objects serve the same purpose which is to instantiate an automation object (COM). To back this up here is the official description of each;

WScript - CreateObject() Method

Creates a COM object

JScript - ActiveXObject Method

Enables and returns a reference to an Automation object

VBScript - CreateObject() Function

Creates and returns a reference to an Automation object

If they were completely the same what would the point of them be? We already have language-specific automation instantiation methods, so what would the point of Wscript.CreateObject() be?

The difference is when called with a second parameter it allows you to specify a prefix that will use to distinguish event handlers for that COM object.

Here is an example taken from this answer that shows how the second argument is used to set a prefix of objIE_ that will then be used to prefix any event handlers associated with that COM object, in this case, the InternetExplorer.Application object.

// JScript
var objIE = WScript.CreateObject("InternetExplorer.Application","objIE_")
objIE.Visible = true

while (objIE.Visible){
    WScript.Sleep(500);
}

function objIE_NavigateComplete2(pDisp, URL){
    WScript.Echo("You just navigated to", URL)
} 

function objIE_OnQuit(){
    boolBrowserRunning = false ;
}

It allows an Internet Explorer instance to be opened and the URL navigated to captured through the bound event, once the Internet Explorer Window is closed the script will end.

So while not identical they do perform the same function of instantiating an Automation (COM) object.

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