>Hi,
>but I want the array start with 0 element, and I loop the client table if the client fullfill some condition,
>I will insert the client code into the array. then how to define the array and insert into the array ?
>
>
>

>PUBLIC ARRAY aClient[0]
>select client
>do while not eof()
>    if substr(Client.clientcode, 1,1)="A"
>      insert to aClient   <- I don't know how to code it for this part.
>      
>    endif
>    skip 1
>enddo
>
>

No, the array can't have zero elements:

PUBLIC ARRAY aClient[1]
select client
lnArrayNumber = 0
do while not eof()
    if substr(Client.clientcode, 1,1)="A"
       lnArrayNumber = lnArrayNumber + 1
       DECLARE aClient[m.lnArrayNumber]
       aClient[m.lnArrayNumber] = 'Something'
    endif
    skip 1
enddo

But BETTER:

SELECT SomethingFromYourTable ;
FROM YourTable;
WHERE substr(Client.clientcode, 1,1)="A";
INTO ARRAY laArray