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4/8/2010

This message maps the index of an item to a unique identifier (ID).

To send this message, call the SendMessagefunction.

Syntax 

lResult = SendMessage( 
   (HWND) hWndControl, 
   (UINT) LVM_MAPINDEXTOID, 
   (WPARAM) wParam, // = (WPARAM) (UINT) 
index;
   (LPARAM) 
lParam	 // = 0; not used, must be zero
);

Parameters

index

UINT that contains the index of an item.

lParam

Must be zero.

Return Value

Returns a unique ID.

Remarks

List-view controls internally track items by index. This can present problems because indexes can change during the control's lifetime.

The list-view control can tag an item with an ID when the item is created. You can use this ID to guarantee uniqueness during the lifetime of the list-view control.

Note:
In a multithreaded environment, the index is only guaranteed on the thread that hosts the list-view control, not on background threads.

Requirements

Header commctrl.h
Windows Embedded CE Windows CE 5.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also