ACC: Automation Object Disappears When Code Finishes Executing
ID: Q161253
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The information in this article applies to:
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Microsoft Access versions 7.0, 97
SYMPTOMS
Moderate: Requires basic macro, coding, and interoperability skills.
When you use Automation to control another application, such as Microsoft
Word or Microsoft Excel, the application quits as soon as your procedure
finishes running.
This article assumes that you are familiar with Visual Basic for
Applications and with creating Microsoft Access applications using the
programming tools provided with Microsoft Access. For more information
about Visual Basic for Applications, please refer to your version of the
"Building Applications with Microsoft Access" manual.
CAUSE
The application quits because its object variable loses scope.
RESOLUTION
If you do not want the Automation server application to close when your
code finishes running, use one of the following methods.
Method 1
Declare the object variable in the Declarations section of your code
module:
- Open the sample database Northwind.mdb.
- Create a module and type the following line in the Declarations section:
Dim xlApp as Object
- Type the following procedure:
Sub LeaveXLOpen1()
Set xlApp = CreateObject("Excel.Application")
xlApp.Visible = True
End Sub
- To test this function, type the following line in the Debug window,
and then press ENTER:
LeaveXLOpen1
Note that Microsoft Excel starts and remains visible after the procedure
stops running. Microsoft Excel quits automatically when you close your
database because that is when the object variable loses scope.
NOTE: If you declare your object variable in the Declarations section of a
form or report module, Microsoft Excel remains open only as long as the
form or report remains open.
Method 2
Declare the object variable as a Static variable at the procedure level:
- Open the sample database Northwind.mdb.
- Create a module and type the following procedure:
Sub LeaveXLOpen2()
Static xlApp as Object
Set xlApp = CreateObject("Excel.Application")
xlApp.Visible = True
End Sub
- To test this function, type the following line in the Debug window,
and then press ENTER:
LeaveXLOpen2
Note that Microsoft Excel starts and remains visible after the procedure
stops running. Microsoft Excel quits automatically when you close your
database because that is when the object variable loses scope.
NOTE: If you declare the Static variable as part of a procedure in a form
or report module, Microsoft Excel remains open only as long as the form or
report remains open.
MORE INFORMATION
Where and how you declare a variable in a code module determines its scope
and its lifetime. Scope is defined as the availability of a variable,
constant, or procedure for use by another procedure. Lifetime is defined as
the time during which a variable retains its value.
When you declare an object variable within a procedure, the variable only
retains its value as long as the procedure is running, as shown in the
example in the "Steps to Reproduce Behavior" section.
Steps to Reproduce Behavior
- Open the sample database Northwind.mdb.
- Create a module and type the following procedure:
Sub OpenAndClose()
Dim xlApp as Object
Set xlApp = CreateObject("Excel.Application")
xlApp.Visible = True
End Sub
- To test this function, type the following line in the Debug window,
and then press ENTER:
OpenAndClose
Note that Microsoft Excel starts and then quits. That is because its
object variable, xlApp, loses scope as soon as the procedure stops
running.
REFERENCES
For more information about the scope and lifetime of variables, search the
Help Index for variables, scope, or variables, lifetime.
For more information about using the CreateObject function, search the
Help Index for CreateObject function.
For more information about declaring Static variables, search the Help
Index for Static statement.
For information about using Microsoft Access as an Automation server,
please see the following article in the Microsoft Knowledge Base:
Q147816
ACC: Using Microsoft Access as an Automation Server
For more information about quitting Microsoft Excel after you run
Automation code, please see the following article in the Microsoft
Knowledge Base:
Q145770
ACC: Automation Does Not Close Microsoft Excel
Additional query words:
Keywords : kbinterop AccCon IntpOlea
Version : WINDOWS:7.0,97
Platform : WINDOWS
Issue type : kbprb