Use of null

[wangui1981]

I have 3 fields am trying to sum.In some parts of the report one of the two field is null so the report does not return the sum. How can I write a formula where if null then zero here is what i have been trying.
if{VVOUCHER.wht} is null then 0
but then when checking for errors the system highlights against 'is' and says 'then is required.

 

[kuekue]

try this :

if(isnull({VVOUCHER.wht}))then 0;

 

[lbass]

(
if isnull({table.field1}) then
0 else
{table.field1}
) +
(
if isnull({table.field2}) then
0 else
{table.field2}
) +
(
if isnull({table.field3}) then
0 else
{table.field3}
)

-LB