Microsoft Access 2010 Bible

Chapter 13: Accessing Data with VBA Code

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At the end of the procedure, txtTaxAmount is set to the curTaxAmount value.

When the Buyer, Tax Location, or Tax Rate controls are changed in frmSales, you use the

AfterUpdate event for the individual control to recalculate the tax amount. Figure 13.18 shows

the code for the txtTaxRate_AfterUpdate event.

FIGURE 13.18

Recalculating a control after a control is updated

The logic implemented in txtTaxRate_AfterUpdate is identical to the logic in fsubSales-

LineItems_AfterUpdate. In fact, you can use the same code for the Buyer and Tax Location

controls as well. The only difference between the code in Figure 13.16 and the code in Figure

13.18 is that the procedure in Figure 13.16 runs whenever a change occurs in the sales line items

subform, while the code in Figure 13.18 runs whenever a change is made to txtTaxRate on the

main form.

Checking the status of a record deletion

Use the form’s AfterDelConfirm event to recalculate the txtTaxAmount control when delet-

ing a line item. The form’s AfterDelConfirm event (shown in Figure 13.19) is similar to the

code for the subform’s AfterUpdate event. Notice however, that txtTaxAmount on the main

sales form is set by this procedure, even though this code runs in fsubSalesLineItems sub-

form embedded on frmSales.

Access always confirms deletions initiated by the user. Access displays a message box asking the

user to confirm the deletion. If the user affirms the deletion, the current record is removed from

the form’s recordset and temporarily stored in memory so that the deletion can be undone if neces-

sary. The AfterDelConfirm event occurs after the user confirms or cancels the deletion. If the

BeforeDelConfirm event isn’t canceled, the AfterDelConfirm event occurs after the delete

confirmation dialog box is displayed. The AfterDelConfirm event occurs even if the

BeforeDelConfirm event is canceled.