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 WM_CHARTOITEM

The WM_CHARTOITEM message is sent by a list box with the LBS_WANTKEYBOARDINPUT style to its owner in response to a WM_CHAR message.

A window receives this message through its WindowProc function.

    LRESULT CALLBACK WindowProc(
      HWND hwnd,       // handle to window
      UINT uMsg,       // WM_CHARTOITEM
      WPARAM wParam,   // key value and caret position
      LPARAM lParam    // handle to list box (HWND)
    );

Parameters

• wParam
The low-order word specifies the value of the key the user pressed. The high-order word specifies the current position of the caret.
• lParam
Handle to the list box.

Return Values

The return value specifies the action that the application performed in response to the message. A return value of –1 or –2 indicates that the application handled all aspects of selecting the item and requires no further action by the list box. A return value of 0 or greater specifies the zero-based index of an item in the list box and indicates that the list box should perform the default action for the keystroke on the specified item.

Remarks

The DefWindowProc function returns –1.

Only owner-drawn list boxes that do not have the LBS_HASSTRINGS style can receive this message.

If a dialog box procedure handles this message, it should cast the desired return value to a BOOL and return the value directly. The DWL_MSGRESULT value set by the SetWindowLong function is ignored.

Requirements

• Windows NT/2000 or later: Requires Windows NT 3.1 or later.
• Windows 95/98/Me: Requires Windows 95 or later.
• Header: Declared in Winuser.h; include Windows.h.

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time