🚀 go-pugleaf

"Adam Versteegen" <no@email.com> wrote in message
news:3ef23b06@newsgroups.borland.com...

> When using ShellExecute or ShellExecuteEx is there
> a way to display the 'open with' windows dialog if
> the file passed in is a non recognised file extension?

ShellExecute() is not smart enough to do that automatically.  Since you have
to explicitally tell it which particular verb to execute for the file,
you'll have to determine that yourself manually before calling
ShellExecute().  You should look in the Registry directly to see what the
available verbs for the file extension are.  If "open" is available, then
use that as normal, otherwise use the shell's built-in "openas" verb
instead.  For example (untested):

    AnsiString ext = ".ext";
    bool isOpenAvailable = false;

    HKEY hKey = NULL
    if( RegOpenKeyEx(HKEY_CLASSES_ROOT, ext.c_str(), 0, KEY_QUERY_VALUE,
&hKey) == ERROR_SUCCESS )
    {
        char progid[256] = {0};
        DWORD dwSize = sizeof(progid);

        RegQueryValueEx(hKey, "", NULL, NULL,
reinterpret_cast<LPBYTE>(progid), &dwSize);
        RegCloseKey(hKey);

        if( progid[0] != '\0' )
        {
            if( RegOpenKeyEx(HKEY_CLASSES_ROOT, progid, 0, KEY_QUERY_VALUE,
&hKey) == ERROR_SUCCESS )
            {
                HKEY hTempKey = NULL;
                isOpenAvailable = ( RegOpenKeyEx(hKey, "shell\\open", 0,
KEY_QUERY_VALUE, &hTempKey) == ERROR_SUCCESS );

                if( hTempKey ) RegCloseKey(hTempKey);
                RegCloseKey(hKey);
            }
        }
    }

    if( isOpenAvailable )
        ShellExecute(NULL, "open", ...);
    else
        ShellExecute(NULL, "openas", ...);


An alternative I have seen posted before, but have not tried myself, is to
just call ShelExecute() with "open" regardless, and then call it with
"openas" only if "open" failed:

    if( ShellExecute(NULL, "open", ...) <= 32 )
        ShellExecute(NULL, "openas", ...);


Gambit