How to open a document programatically

Here is some example code illustrating how to open a document file:

   CComPtr<Documents> pDocs = nullptr ;

   HRESULT hRes = pInvApp->get_Documents (&pDocs) ;

   if (FAILED(hRes) || (pDocs == nullptr)) {

       ShowCOMError(hRes,L"RunTest,get_Documents failed ");

       return ;

   }

   CComPtr<Document> pDoc;

   hRes = pDocs->Open (CComBSTR (L"C:\\PARTS\\MyPart.Ipt"),VARIANT_TRUE,&pDoc) ;

   if (FAILED(hRes) || (pDocs == nullptr)) {

       ShowCOMError(hRes,L"RunTest, Open failed ");

       return ;

   }

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