Storing a calculated control.??

[Durien512]

if i have formula in a text box can that calculation be stored in a table???

example

sales total

sales tax

grand total

where grand total = sales tax+sales total

if the control is bounded to a field in a table once the formula is entered doesnt it loose the connection with the field???

right now when i enter a formula in a control it will no longer store it in the table but it will only show the result in the actual form..???

[RuralGuy]

In order to store the value calculated in your TextBox you will need to add some code to the Form's BeforeUpdate event. You already know that it is bad practice to store calculated values unless there is some historical reason, as you have, where the sales tax rate might change. In the BeforeUpdate event of the form put something like:
Me![TotalSalesField] = Me!txtTotalSaleCalcControl

Using your control and field names of course.

[reclusivemonkey]

The calculated field is only shown in the form. You will need to use an update query to add the value to the table.

[neileg]

Just to reiterate:

You don't store things that can be calculated from other stored data. If, as RuralGuy suggests, the tax rate may change, then it is legitimate to store the amount of the tax calculated. However, since grand total will always be sales total plus tax total, you should not save that value.

[Durien512]

Thanks...makes sense...