RaiseError Macro Action

The RaiseError action throws an exception that can be handled by the OnError macro action.

Note

The RaiseError action is available only in Data Macros.

Setting

The RaiseError action has the following arguments.

Argument	Required	Description
Error Number	Yes	A number or an expression that resolves to the Long data type.
Error Description	No	A string expression that describes the error.

Remarks

If the RaiseError action is called in a Before Change or Before Delete macro event, the event is cancelled.

If there is not an active OnError statment that is handling errors, then the error thrown by the RaiseError action is added to the USysApplicationLog system table. When the RaiseError action to writes to the USysApplicationLog table, the Category column is automatically set to Execution.

To see the USysApplicationLog table, use the following steps:

1. Click the File menu, and then click Options.

2. In the Access Options dialog box, click the Current Database tab.

3. In the Navigation section, click Navigation Options.

4. In the Navigation Options dialog box, click Show System Objects, and then click OK.

5. Click OK to dismiss the Access Options dialog box.

Example

The following example shows how to use the RaiseError action to cancel the Before Change data macro event. When the AssignedTo field is updated, a LookupRecord data block is used to determine whether the assigned technician is currently assigned to an open service request. If this is true, then the Before Change event is cancelled and the record is not updated.

Sample code provided by: The Microsoft Access 2010 Programmer’s Reference | About the Contributors

/* Get the name of the technician  */
Look Up A Record In tblTechnicians
    Where Condition =[tblTechnicians].[ID]=[tblServiceRequests].[AssignedTo]
SetLocalVar
    Name TechName
    Expression [tblTechnicians].[FirstName] & " " & [tblTechnicians].[LastName]
/* End LookUpRecord  */

If Updated("AssignedTo") Then
    Look Up A Record In tblServiceRequests
        Where Condition SR.[AssignedTo]=tblServiceRequests[AssignedTo] And 
            SR.[ID]<>tblServiceRequests.[ID] And IsNull(SR.[ActualCompletionDate])
        Alias SR
        RaiseError
            Error Number 1234
            Error Description ="Cannot assign a request to the specified technician: " & [TechName]

End If

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