Microsoft Foundation Classes (mfc.hlp) (Table of Contents; Topic list)
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CWnd::OnCompareItem
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──Microsoft Foundation Classes──────────────────────────────────────────────
 
  afx_msg int OnCompareItem ( LPCOMPAREITEMSTRUCT  lpCompareItemStruct  );
 
  Parameter             Description
 
  <lpCompareItemStruct> Contains a long pointer to a ◄COMPAREITEMSTRUCT►
                        data structure that contains the identifiers and
                        application-supplied data for two items in the
                        combo or list box.
 
  Remarks
 
  Override this member function in your derived class to handle the
  ◄WM_COMPAREITEM► message.
 
  Use the overridden member function to specify the relative position of a
  new item in a sorted owner-draw combo or list box.
 
  If a combo or list box is created with the ◄CBS_SORT► or ◄LBS_SORT►
  style, Windows sends the combo-box or list-box owner a WM_COMPAREITEM
  message whenever the application adds a new item.
 
  The <lpCompareItemStruct> parameter is a long pointer to a
  ◄COMPAREITEMSTRUCT► data structure that contains the identifiers and
  application-supplied data for two items in the combo or list box.
  OnCompareItem should return a value indicating which of the items should
  appear before the other. Typically, Windows makes this call several
  times until it determines the exact position for the new item.
 
  This message-handler member function calls the ◄Default► member
  function.
 
  Return Value
 
  Indicates the relative position of the two items. It may be any of the
  following values:
 
  Value   Meaning
 
  -1      Item 1 sorts before item 2.
 
  0       Item 1 and item 2 sort the same.
 
  1       Item 1 sorts after item 2.
 
  See Also
 
  ◄COMPAREITEMSTRUCT►, ◄WM_COMPAREITEM►, ◄CWnd::Default►
 
 
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