Salut.
  Sunt un incepator in FoxPro si m-am lovit de o mica problema.
  M-am apucat sa fac un program despre clientii unei societati care furnizeaza energie electrica (ceva asemanator ENEL) si nu stiu cum sa aflu perioada de calcul (nr_zile) scazand din data curenta ultima data inregistrata (data_cit) pentru o anumita serie_c (serie contor) (ex. 123456).
  Acesta este tabelul cu inregistrarile (index.dbf):

client	data_cit	nr_zile	index_cit	consum
ionescu	15-01-2011		19356
ionescu	16-03-2011		19653	297
popescu	03-01-2011		10247
popescu	04-03-2011		10421	174
vasilescu	25-01-2011		32315
vasilescu	26-03-2011		32415	100

  Iar acesta este programul index.prg :

CLEAR
SET TALK OFF
CLOSE databases
CLOSE TABLES all
SET DATE DMY
SET CENTURY on
SELECT 1
USE clienti
SELECT 2
USE index
SELECT 3
USE tarife
SELECT 4
USE taxe

DEFINE WINDOW w FROM 10,60 TO 64,114
ACTIVATE WINDOW w
SELECT 1
accept 'Numele abonatului=' to mnume
SET EXACT ON
LOCATE FOR nume=mnume
IF FOUND() then
SELECT 2
?' Ultima data',data_cit
?' Data citire',DATE()
?' Index vechi=',index_cit
input ' Index nou  =      ' to index_nou
?
con=index_nou-index_cit
?' Consum='+ltrim(STR(con)),'KWH'
?
?' Perioada facturare=        ',data_cit,'-',date()
?
z=DATE()-data_cit
?' Numar zile='+LTRIM(STR(z)),'ZILE'
?
SELECT 3
valc=con*cr
?' Valoare=                    ',ROUND(valc,2),'LEI'
tva=valc*24/100
?' Valoare T.V.A.=             ',ROUND(tva,2),'LEI'
?
rez1=tarife.rez*z
?' Valoare rezervare=          ',ROUND(rez1,2),'LEI'
tva_rez=rez1*24/100
?' T.V.A. rezervare=           ',ROUND(tva_rez,2),'LEI'
?
val_acc=acc*con
?' Valoare acciza=             ',ROUND(val_acc,2),'LEI'
tva_acc=val_acc*24/100
?' T.V.A. acciza=              ',ROUND(tva_acc,2),'LEI'
?
SELECT 4
?' Taxa radio=                        ',ROUND(radio,2),'LEI'
?
?' Taxa TV=                           ',ROUND(tv,2),'LEI'
?
total=valc+rez1+val_acc
?' Valoare factura fara T.V.A.=',ROUND(total,2),'LEI'
total_tva=tva+tva_acc+tva_rez
?' Valoare T.V.A. factura=     ',ROUND(total_tva,2),'LEI'
?
total_f=total+total_tva+radio*2+tv*2
?' Valoare factura=            ',ROUND(total_f,2),'LEI'
ENDIF
?

lady=" "
do iesire with lady,"Doresti sa mai continui ?"
if lady="D" then
        close data
        do index
else
   close databases
    return
ENDIF

 PROCEDURE iesire

PARAMETER intreb,mess1

DEFINE WINDOW day FROM 64,63 TO 69.1,111.8 ;
COLOR w+/gr  SHADOw
ACTIVATE WINDOW day
@0,1 SAY PADC(mess1,WCOLS());
   PICTURE "@I"
@2,10 GET intreb;
   PICTURE "@*HT <  \<Da  >;<  \<Nu  >";
   SIZE 1,10,5;
   MESSAGE " "
READ
intreb=SUBSTR(intreb,4,1)
DEACTIVATE WINDOW day
DEACTIVATE WINDOW w
RETURN

  Cu speranta ca poate m-am facut inteles astept ajutor din partea ASILOR in ale Visual FoxPro-ului.