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Hi,<br />
<br />
i want to call an activex control from my dll code but when i use the interface of activex control in my dll then it says <br />
&quot;undeclared identifier&quot;.<br />
i know my dll code doesn't find the declaration of interface's pointer.<br />
can you please tell me which header files or libraries i have to include so that i can get the pointer of my activex control.
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<div class="content wysiwyg-content">
Hello,<br />
<br />
I am making a C program which should use an ActiveX control.<br />
<br />
I have an ActiveX control and i know its CLSID, I want to use it so I do :<br />
<br />
hr = CoInitializeEx ( NULL, COINIT_MULTITHREADED );<br />
<br />
then<br />
<br />
hr = CoCreateInstance ( &amp;clsid, <br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NULL, <br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;CLSCTX_INPROC_SERVER, <br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&amp;IID_IUnknown, //(REFIID) &amp;giid, <br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&amp;ppv );<br />
<br />
If I do so ... I have a link error LNK2001 telling me : unresolved external symbol IID_IUnknown<br />
<br />
When I am using an ActiveX control is it a proper manner user IID_IUnknown as the REFIID, if not what should i use as the REFIID and how do I define it.<br />
<br />
<br />

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Hello,

I am making a C program which should use an ActiveX control.

I have an ActiveX control and i know its CLSID, I want to use it so I do :

hr = CoInitializeEx ( NULL, COINIT_MULTITHREADED );

then

hr = CoCreateInstance ( &clsid, 
		NULL, 
		CLSCTX_INPROC_SERVER, 
		&IID_IUnknown, //(REFIID) &giid, 
		&ppv );

If I do so ... I have a link error LNK2001 telling me : unresolved external symbol IID_IUnknown

When I am using an ActiveX control is it a proper manner user IID_IUnknown as the REFIID, if not what should i use as the REFIID and how do I define it.




Hi,

i want to call an activex control from my dll code but when i use the interface of activex control in my dll then it says 
&quot;undeclared identifier&quot;.
i know my dll code doesn&#39;t find the declaration of interface&#39;s pointer.
can you please tell me which header files or libraries i have to include so that i can get the pointer of my activex control.

Instanciating an ActiveX control into a C program

Hello,

I am making a C program which should use an ActiveX control.

I have an ActiveX control and i know its CLSID, I want to use it so I do :

hr = CoInitializeEx ( NULL, COINIT_MULTITHREADED );

then

hr = CoCreateInstance ( &amp;clsid, 
		NULL, 
		CLSCTX_INPROC_SERVER, 
		&amp;IID_IUnknown, //(REFIID) &amp;giid, 
		&amp;ppv );

If I do so ... I have a link error LNK2001 telling me : unresolved external symbol IID_IUnknown

When I am using an ActiveX control is it a proper manner user IID_IUnknown as the REFIID, if not what should i use as the REFIID and how do I define it.




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