Appendix F: Object Identifier Values for OBJID_QUERYCLASSNAMEIDX

When OLEACC sends a WM_GETOBJECT message with the lParam parameter set to OBJIDQUERYCLASSNAMEIDX, many standard USER or common controls (COMCTL) return one of the following values.

USER or common control Return value
Listbox 65536+0
Button 65536+2
Static 65536+3
Edit 65536+4
Combobox 65536+5
Scrollbar 65536+10
Status 65536+11
Toolbar 65536+12
Progress 65536+13
Animate 65536+14
Tab 65536+15
Hotkey 65536+16
Header 65536+17
Trackbar 65536+18
Listview 65536+19
Updown 65536+22
ToolTips 65536+24
Treeview 65536+25
RichEdit 65536+28


Only USER and Windows common controls (COMCTL) will return one of the values from the table. If a window returns 0 in response to this message, the window may be one of the following:

  • A custom control
  • A control other than one of the controls in the previous table
  • An old version of a system control that does not recognize the WM_GETOBJECT message

If a window returns 0, clients may need to use RealGetWindowClass or GetClassName. You can use these functions to determine the type of control based on class name.

In general, clients can use the information provided by OLEACC.