Programming |  Windows Programming |  BM_SETCHECK

BM_SETCHECK

Sets the check state of a radio button or check box.

Syntax

To send this message, call the SendMessage function as follows.

    lResult = SendMessage(      // returns LRESULT in lResult     
       (HWND) hWndControl,      // handle to destination control     
       (UINT) BM_SETCHECK,      // message ID     
       (WPARAM) wParam,         // = (WPARAM) () wParam;    
       (LPARAM) lParam          // = 0; not used, must be zero 
    );   

Parameters

• wParam
  The check state. This parameter can be one of the following values.
  • BST_CHECKED
    Sets the button state to checked.
  • BST_INDETERMINATE
    Sets the button state to grayed, indicating an indeterminate state. Use this value only if the button has the BS_3STATE or BS_AUTO3STATE style.
  • BST_UNCHECKED
    Sets the button state to cleared.
• lParam
  This parameter is not used.

Return Value

This message always returns zero.

Remarks

The BM_SETCHECK message has no effect on push buttons.

Message Information

• Header Declared in Winuser.h, include Windows.h
• Minimum operating systems Windows 95, Windows NT 3.1