From String to Number

Hello.

I have problem with convert data from String to Number. All data with comma don't convert to number.

It's nvarchar(40) in database.

My function:

shared numberVar sum_dur_op;

shared datetimeVar sum_date_op;

if not isNull({DM_UNDERWATER_DETAIL.cost_code}) and NumericText({DM_UNDERWATER_DETAIL.cost_code}) then (

    sum_dur_op := sum_dur_op + ToNumber({DM_UNDERWATER_DETAIL.cost_code});

    if not isNull({DM_UNDERWATER_OP.start_date}) or year({DM_UNDERWATER_OP.start_date}) <> 0 then

        sum_date_op := DateAdd("h", sum_dur_op, {DM_UNDERWATER_OP.start_date});

);

I have got next results:

sum_dur_op      sum_date_op        

1.68      14.04.2015 0:00:00

1.92      14.04.2015 0:00:00

6      14.04.2015 6:00:00

9.6      14.04.2015 6:00:00

1.92      14.04.2015 6:00:00

I try function Val and have got the same results.