The typed text is stored in This.DisplayValue.

LPARAMETERS nKeyCode, nShiftAltCtrl

IF nKeyCode = 13  THEN && Enter
	lExists = .F.
	FOR i = 1 TO this.ListCount 
		IF this.ListItem(i) = ALLTRIM(This.DisplayValue)
			lExists = .T.
                        EXIT
		ENDIF 
	ENDFOR 	
	IF NOT lExists 
		this.AddItem(This.DisplayValue)
	ENDIF 		
    thisform.oWeb.Navigate(This.DisplayValue) 
ENDIF

Sergey thank you very much for the feedback.

Zakaria al Azhar