{"id":63,"date":"2009-07-15T20:47:49","date_gmt":"2009-07-16T00:47:49","guid":{"rendered":"http:\/\/www.northatlantawebdesign.com\/?p=63"},"modified":"2010-07-09T09:08:06","modified_gmt":"2010-07-09T13:08:06","slug":"access-microsoft-excel-2007-com-api-through-microsoft-active-accessibility","status":"publish","type":"post","link":"https:\/\/www.northatlantawebdesign.com\/index.php\/2009\/07\/15\/access-microsoft-excel-2007-com-api-through-microsoft-active-accessibility\/","title":{"rendered":"Access Microsoft Excel 2007 COM API through Microsoft Active Accessibility"},"content":{"rendered":"

A couple days ago I showed you how to access the Microsoft Word 2007<\/a> COM API through Microsoft Active Accessibility (MSAA). Today, I’m going to switch it up just a little bit, and use the same method to access the Microsoft Excel 2007<\/a> COM API. Again, we’ll be using AccesssibleObjectFromWindow to get at the main Excel::Window object. From that object, you can obtain the Excel Application, and Excel Workbook objects. Some documentation from Microsoft can be found here<\/a>.<\/p>\n

<\/p>\n

First we obtain the hwnd of the Microsoft Excel Process:<\/p>\n

\r\n\/\/The main window in Microsoft Excel has a class name of XLMAIN\r\nHWND excelWindow = FindWindow(L"XLMAIN", NULL);\r\n<\/pre>\n
We can then traverse the child windows until we find the one with classname EXCEL7:<\/p>\n
\r\n\/\/Use the EnumChildWindows function to iterate through all child windows until we find EXCEL7\r\nEnumChildWindows(excelWindow, (WNDENUMPROC) EnumChildProc, (LPARAM)1);\r\n<\/pre>\n
\r\nstatic BOOL EnumChildProc(HWND hwnd, LPARAM)\r\n{\r\n     WCHAR szClassName[64];\r\n     if(GetClassNameW(hwnd, szClassName, 64))\r\n     {\r\n          if(_wcsicmp(szClassName, L"EXCEL7") == 0)\r\n          {\r\n               \/\/Get AccessibleObject\r\n               Excel::Window* pWindow = NULL;\r\n               HRESULT hr = AccessibleObjectFromWindow(hwnd, OBJID_NATIVEOM, __uuidof(Excel::Window), (void**)&pWindow);\r\n               if(hr == S_OK)\r\n               {\r\n                    \/\/Excel object is now in pWindow pointer, from this you can obtain the document or application\r\n                    Excel::_Application* pApp = NULL;\r\n                    pWindow->get_Application(&pApp);\r\n                    pWindow->Release();\r\n               }\r\n               return false;     \/\/ Stops enumerating through children\r\n          }\r\n     }\r\n     return true;\r\n}\r\n<\/pre>\n
Next we obtain our Excel::Window object through AccessibleObjectFromWindow:<\/p>\n
\r\n\/\/Get AccessibleObject\r\nExcel::Window* pWindow = NULL;\r\nHRESULT hr = AccessibleObjectFromWindow(hwnd, OBJID_NATIVEOM, __uuidof(Excel::Window), (void**)&pWindow);\r\n<\/pre>\n
That’s it!  We now have our Excel::Window COM Object.  From this object we can obtain the Excel::Application and Excel::Workbook objects, allowing us full interaction with the active document.  So with just a few lines of code, we now have access to automate an Excel 2007 document.<\/p>\n
Full source code:<\/p>\n
\r\n#include <windows.h>\r\n#include <oleacc.h>\r\n#include "msexcel.h"\r\n\r\nstatic BOOL EnumChildProc(HWND hwnd, LPARAM)\r\n{\r\n     WCHAR szClassName[64];\r\n     if(GetClassNameW(hwnd, szClassName, 64))\r\n     {\r\n          if(_wcsicmp(szClassName, L"EXCEL7") == 0)\r\n          {\r\n               \/\/Get AccessibleObject\r\n               Excel::Window* pWindow = NULL;\r\n               HRESULT hr = AccessibleObjectFromWindow(hwnd, OBJID_NATIVEOM, __uuidof(Excel::Window), (void**)&pWindow);\r\n               if(hr == S_OK)\r\n               {\r\n                    \/\/Excel object is now in pWindow pointer, from this you can obtain the document or application\r\n                    Excel::_Application* pApp = NULL;\r\n                    pWindow->get_Application(&pApp);\r\n                    pWindow->Release();\r\n               }\r\n               return false;     \/\/ Stops enumerating through children\r\n          }\r\n     }\r\n\t return true;\r\n}\r\nint main( int argc, CHAR* argv[])\r\n{\r\n     \/\/The main window in Microsoft Excel has a class name of XLMAIN\r\n     HWND excelWindow = FindWindow(L"XLMAIN", NULL);\r\n\r\n     \/\/Use the EnumChildWindows function to iterate through all child windows until we find _WwG\r\n     EnumChildWindows(excelWindow, (WNDENUMPROC) EnumChildProc, (LPARAM)1);\r\n\r\n     return 0;\r\n}\r\n<\/pre>\n
Useful Links for this post:<\/p>\n