SHGetFileInfoW Returns the system index number of the icon

Question

Now I have the index number of the icon (say 81).

How to get the icon using the index number,(I know that SHGetFileInfoW can get the icon directly),

I want to save the index and call it when I need it

Answer 1

For example, a test of Notepad icon :

                    SHFILEINFO sfi = { 0 };
                    HIMAGELIST hImageList = (HIMAGELIST)SHGetFileInfo(L"C:\\WINDOWS\\system32\\notepad.exe", 0, &sfi, sizeof(sfi), SHGFI_SYSICONINDEX);
                    if (hImageList)
                    {
                        int nX = 10, nY = 10;
                        HDC hDC = GetDC(NULL);
                        DrawIconEx(hDC, nX, nY, ImageList_GetIcon(hImageList, sfi.iIcon, ILD_NORMAL), 0, 0, 0, NULL, DI_NORMAL);
                        ReleaseDC(NULL, hDC);
                    }

Answer 2

According to documentation and some articles, you can obtain the system image list using a code like this:

SHFILEINFO unused;
HIMAGELIST hSysImgList = (HIMAGELIST)SHGetFileInfo(
       "C:", 
       FILE_ATTRIBUTE_NORMAL, 
       &unused, 
       sizeof(SHFILEINFO), 
       SHGFI_USEFILEATTRIBUTES | SHGFI_SYSICONINDEX | SHGFI_ICON);

The name of the file does not matter. Maybe you should also specify the SHGFI_SMALLICON flag.

Then use ImageList_GetIcon to get the icon by index.