Help Is Null - no data

[hessleroader]

Hi all

i have a form that get a value from a query which i use the dmax funtion for which works fine

but i want to do this but it is not working

if me.invoiceno - isnull then
me.invoiceno = dmax ("invoiceno","query1")+1

but i am still getting a blank field, any ideas

 

[Kempes]

try

if isnull(me.invoiceno) then
etc....

 

[hessleroader]

thanks worked

simon