Sample Code (in VB) for your reference:

Dim objImage
Set objImage= CreateObject("AutoDWGCompare.CompareDWG")

objImage.Compare "version1.dwg","version2.dwg"

 

Sample Code (in VC) for your reference:

#import "D:\\AutoDWGCompare\\CompareDWGX.ocx" named_guids rename_namespace("AutoDWGCompare")

{
CString str1, str2;

CComPtr<AutoDWGCompare::ICompareDWG> conv;
HRESULT hResult = conv.CoCreateInstance(AutoDWGCompare::CLSID_CompareDWG);

str1 = m_strInputFile1;
str2 = m_strInputFile2;
conv->raw_Compare(str1.AllocSysString(), str2.AllocSysString());
}