Counting values then display the sum

[shod90]

Dear Gents,
Um trying to make an app. which manage orders for market.
So , If the user chooses say 4 items , Then it should display the total at the bottom of the page dynamically , and if the user remove any item it again updates automatically .
How to do that process ?

[sstiebinger]

I'm assuming the items will be displayed in a continuous form, then simply place a text box in the form header or form footer (NOT the page header/footer).
If the field for the individual items were "Price" your text box control source would be

=Sum([Price])

then be sure to set the format for the text box to Currency.