data lost

[Holly]

I have a stored procedure and I called it from my c#
application. The use case is:
1)user selects some affiliate codes from a form.
2)the code list, e.g.('aff1',aff 2') will be used as input
of the stored procedure.
Select AffiliateCode,b alance from RCS_Affiliates where
affiliateCode in ('aff1',aff2'.. )
2)selected code and balance will be inserted into another
table.

When I called my stored procedure, I have
this problem:
If the list has 2 elements, none is
selected. If it has more than 2 elements, the first and
the last one will not be selected.
E.g. if my input
string is 'a,b,c,d', Only b and c are handled. The stored
procedure works fine if it is called from the SQL
analyzer. The problem only occurs when the stored
procedure is called from the C# application. I guess it
is somewhere in my C# code.


Here is the code:
SqlCommand cmd = null;
cmd=new SqlCommand
("RCS_CreateAff iliatePayouts", conn);
cmd.CommandType = CommandType.Sto redProcedure;
SqlParameter cons = cmd.Parameters. Add
("@cons",
SqlDbType.VarCh ar, 8000);
cons.Direction = ParameterDirect ion.Input;
cons.Value = "'a,b,c,d'" ;
cmd.ExecuteNonQ uery ();


The stored procedure is like:

CREATE PROCEDURE RCS_CreateAffil iatePayouts
@cons varchar(8000)

AS
Declare @type int

set @type=2


INSERT RCS_Payouts
SELECT CURRENT_TIMESTA MP,
balance, @type, AffiliateCode
FROM RCS_Affiliates a1
INNER JOIN iter_charlist_t o_table(@cons, DEFAULT) s1
ON a1.AffiliateCod e= s1.code ;
GO

Thanks.