You can use the CancelEvent action to cancel the event that caused Access to run the macro containing this action. The macro name is the setting of an event property such as BeforeUpdate, OnOpen, OnUnload, or OnPrint.
Note: The CancelEvent macro action is not available in Access web apps.
Setting
The CancelEvent action doesn't have any arguments.
Remarks
In a form, you typically use the CancelEvent action in a validation macro with the BeforeUpdate event property. When a user enters data in a control or record, Access runs the macro before adding the data to the database. If the data fails the validation conditions in the macro, the CancelEvent action cancels the update process before it starts.
Often, you use this action with the MsgBox action to indicate that the data has failed the validation conditions and to provide helpful information about the kind of data that should be entered.
The following events can be canceled by the CancelEvent action.
ApplyFilter | Dirty | MouseDown |
BeforeDelConfirm | Exit | NoData |
BeforeInsert | Filter | Open |
BeforeUpdate | Format | |
DblClick | KeyPress | Unload |
Delete |
Note: You can use the CancelEvent action with the MouseDown event only to cancel the event that occurs when you right-click an object.
If a control's OnDblClick event property setting specifies a macro containing the CancelEvent action, the action cancels the DblClick event.
For events that can be canceled, the default behavior for the event (that is, what Access typically does when the event occurs) occurs after the macro for the event runs. This enables you to cancel the default behavior. For example, when you double-click a word that the insertion point is on in a text box, Access normally selects the word. You can cancel this default behavior in the macro for the DblClick event and perform some other action, such as opening a form containing information about the data in the text box. For events that can't be canceled, the default behavior occurs before the macro runs.
Note: If a form's OnUnload event property specifies a macro that carries out a CancelEvent action, you won't be able to close the form. You must either correct the condition that caused the CancelEvent action to be carried out or open the macro and delete the CancelEvent action. If the form is a modal form, you won't be able to open the macro.
To carry out the CancelEvent action in a Visual Basic for Applications (VBA) module, use the CancelEvent method of the DoCmd object.
Example
Validate data by using a macro
The following validation macro checks the postal codes entered in a Suppliers form. It shows the use of the StopMacro, MsgBox, CancelEvent, and GoToControl actions. A conditional expression checks the country/region and postal code entered in a record on the form. If the postal code is not in the right format for the country/region, the macro displays a message box and cancels saving the record. It then returns you to the Postal Code control, where you can correct the error. This macro should be attached to the BeforeUpdate property of the Suppliers form.
Condition | Action | Arguments: Setting | Comment |
IsNull([CountryRegion]) | StopMacro | If CountryRegion is Null, postal code can't be validated. | |
[CountryRegion] In ("France","Italy","Spain") And Len([Postal Code]) <> 5 | MsgBox | Message: The postal code must be 5 characters. Beep: Yes Type: Information Title: Postal Code Error | If the postal code isn't 5 characters, display a message. |
... | CancelEvent | Cancel the event. | |
GoToControl | Control Name: PostalCode | ||
[CountryRegion] In ("Australia","Singapore") And Len([Postal Code]) <> 4 | MsgBox | Message: The postal code must be 4 characters. Beep: Yes Type: Information Title: Postal Code Error | If the postal code isn't 4 characters, display a message. |
... | CancelEvent | Cancel the event. | |
GoToControl | Control Name: PostalCode | ||
([CountryRegion] = "Canada") And ([Postal Code] Not Like"[A-Z][0-9][A-Z] [0-9][A-Z][0-9]") | MsgBox | Message: The postal code is not valid. Example of Canadian code: H1J 1C3 Beep: Yes Type: Information Title: Postal Code Error | If the postal code isn't correct for Canada, display a message. (Example of Canadian code: H1J 1C3) |
... | CancelEvent | Cancel the event. |
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