The container control sends a WM_CONTROL (in Container Controls) message with the CN_ENDEDIT notification code to its owner whenever direct editing of container text has ended.

param1
     USHORT        id            /*  Container control ID. */
     USHORT        CN_ENDEDIT    /*  Notification code. */

param2
     PCNREDITDATA  pCnrEditData  /*  Pointer to the CNREDITDATA structure. */