calculations!!

[arab]

hey ..
am having BIG problems with my data base
this is my situation:
i am entering all my data in a form, .. i need to know if there is a way i could calculate a sum in a feild.. kind of like excel
the reason for wanting to do this is bcz..
wen i enter an amount , i need to calculate the VAT.
for example
some invoices have two items.. one item includes vat, the other item does not include VAT
Item 1=50 + vat
item 2 =50
so i would need to do something along the lines of this :-
50*0.175+50
bareing in mind tht the items prices are changable so therefore i can not enter a normal formula in query or the forms control source
maybe i could do a default value, so that i can change my values? the question is how?
if anyone has a solution too my problem i wud more than appreciate it
also i am not very good at access, so please explain to the fullest :
regards Lana

 

[Rabbie]

Hi Lana

You can do this by having an unbound field on your form and populating this field by using a formula to pick up the value and multiply it by the VAT rate.

so in the field you would input something like

= me.VatableTotal*1.175

 

[arab]

hey Rabbie thank you for your reply..
by doing what you just instructed, will this allow me to change the value of anything i desired to?
or is this something fixed and not changeable?

 

[henkus]

I suggest having on field in table that holds the price excl. VAT (PriceExclVAT), and one with the VAT (VAT) value (i.e. 0,175 or 0 or whatever).
Calculated field then has formula:
=[PriceExclVAT]*(1+[VAT])

If you change VAT or Price, the calculated field will instantly update to reflect the new value.

/henkus

 

[arab]

hey thanks for your reply
were do i write that formula? is it in forms properties, or queires design view?

 

[henkus]

Control source field in properties of the TextBox

/henkus