Determine the registered application for an extension

Question

I've got a file extension and I'd like to get the name of the application (if there is one) that will be invoked when I ShellExecute a file of that type. This is a WTL/C++ app. Is there any sample code out there that does this?

Thanks!

Answer 1

twk,

You're probably looking for the Win32 AssocQueryStringByKey Function.
http://msdn.microsoft.com/en-us/library/bb773473(VS.85).aspx

The ASSOCSTR value that specifies the type of string that is to be returned:

typedef enum {
    ASSOCSTR_COMMAND = 1,
    ASSOCSTR_EXECUTABLE,
    ASSOCSTR_FRIENDLYDOCNAME,
    ASSOCSTR_FRIENDLYAPPNAME,
    ASSOCSTR_NOOPEN,
    ASSOCSTR_SHELLNEWVALUE,
    ASSOCSTR_DDECOMMAND,
    ASSOCSTR_DDEIFEXEC,
    ASSOCSTR_DDEAPPLICATION,
    ASSOCSTR_DDETOPIC,
    ASSOCSTR_INFOTIP,
    ASSOCSTR_QUICKTIP,
    ASSOCSTR_TILEINFO,
    ASSOCSTR_CONTENTTYPE,
    ASSOCSTR_DEFAULTICON,
    ASSOCSTR_SHELLEXTENSION,
    ASSOCSTR_DROPTARGET,
    ASSOCSTR_DELEGATEEXECUTE,
    ASSOCSTR_MAX
} ASSOCSTR;

My guess is that you want ASSOCSTR_FRIENDLYAPPNAME.

Answer 2

DWORD dwSize = 255;
TCHAR sBuffer[MAX_PATH] = {0};
HRESULT hr = AssocQueryString(0, ASSOCSTR_EXECUTABLE, _T(".htm"), _T("Open"), sBuffer, &dwSize);
CString csExt;
csExt.Format(_T("%s"), sBuffer);
AfxMessageBox(csExt);

Answer 3

Sorry, no code, but some useful information. See this related question: how-does-vista-generate-the-icon-for-documents-associated-to-my-application

It asked about icons, but it turns out the program associated to an extension is stored in the same place in the registry as the icon for that extension.

Answer 4

自1995年以来就是Win32常见问题解答（Shell，请参见Google网上论坛，Win32）