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    <p>In order to have multiple <code>IDispatch</code>-derived interfaces implemented on a single object, to be accessible from scripting environment you should rather implement <code>IDispatchEx</code> and have its methods called once a call from script is taking place. </p> <p>The problem you are facing is caused by the fact that script queries for your <code>IDispatch</code> first, and both your <code>IDispatch</code>-derived interfaces return the same "main" <code>IDispatch</code> leaving no chance for methods of other interfaces to be accessible.</p> <p>When VBS host is about to call a method on your object, it first queries <code>IDispatchEx</code>. If found, the calls are delivered via <code>IDispatchEx::InvokeEx</code> and your COM Class can internally route the call to the proper <code>IDispatch</code> implementation, both private or forward to external/inner object.</p> <p>In case <code>IDispatchEx</code> is not found, it looks for <code>IDispatch</code> and there you are in trouble because it sees only your "main" interface. That is, the workaround for you is to implement <code>IDispatchEx</code>. You can do it either way: implement right on your COM class, or instead create a proxy class to accept scripting calls via <code>IDispatchEx::InvokeEx</code> and forward to correct <code>IDispatch</code> in your code.</p> <p>Example: Both <code>A</code> and <code>B</code> classes implement <code>IX</code> and <code>IY</code> interfaces, <code>B</code> additionally implements <code>IDispatchEx</code>. Interface methods are <code>IX::X1</code>, <code>IY::Y1</code>.</p> <pre class="lang-vb prettyprint-override"><code>On Error Resume Next Set A = CreateObject("Test.A") WScript.Echo A.X1 ' Success, via IX::Invoke WScript.Echo A.Y1 ' Failure, A's IDispatch is IX's parent and does not have Y1 method Set B = CreateObject("Test.B") WScript.Echo B.X1 ' Success, via IDispatchEx::InvokeEx WScript.Echo B.Y1 ' Success, via IDispatchEx::InvokeEx </code></pre>
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    1. POIs it posible to perform QueryInterface on behalf of VBScript
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    1. COthank you for your answer, it made me realise that my original question needed clarifying. As a result I have edited the question to explain my requirement better. From what i have read about IDispatchEx the interface is there to support expando objects. What i need is to be able to take an existing COM object with multiple interfaces and use them in VB Script. Let me know if I’m still not making sense :)
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    2. COSee updated answer above. VBS host asks if you have `IDispatchEx` so if you happen to have one, the host will not even look for your `IDispatch` interfaces anymore and you will be able to handle all method calls, even those you don't really have on interfaces ("dynamic methods").
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    3. COYes, that works as a way around the issue, but I already have a work around. I really want to know if it is possible to return an arbitrary interface to a VBScript client. Also I want to know how to do it. I know I can return a specific interface that is not the default interface but that would involve creating a method for each interface I want to cast to. ...
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