ID: Q141693
The scope of a variable is determined at the time the variable is declared. In Microsoft Visual Basic for Applications, the three scopes available for variables are procedure, module, and public. The "More Information" section of this article describes each scope in detail.
A local variable with procedure scope is recognized only within the procedure in which it is declared. A local variable can be declared with a Dim or Static statement.
Dim:
When a local variable is declared with the Dim statement, the variable remains in existence only as long as the procedure in which it is declared is running. Usually, when the procedure is finished running, the values of the procedure's local variables are not preserved, and the memory allocated to those variables is released. The next time the procedure is executed, all of its local variables are reinitialized.
For example, in the following sample macros, "Example1" and "Example2," the variable X is declared in each of the modules. Each variable X is independent of the other--the variable is only recognized within its respective procedure.
Sub Example1()
Dim X As Integer
' Local variable, not the same as X in Example2.
X = 100
MsgBox "The value of X is " & X
End Sub
Sub Example2()
Dim X As String
' Local variable, not the same as X in Example1.
X = "Yes"
MsgBox "The answer is " & X
End Sub
A local variable declared with the Static statement remains in existence the entire time Visual Basic is running. The variable is reset when any of the following occur:
Sub RunningTotal()
Static Accumulate
' Local variable that will retain its value after the module
' has finished executing.
num = Application.InputBox(prompt:="Enter a number: ", Type:=1)
Accumulate = Accumulate + num
MsgBox "The running total is " & Accumulate
End Sub
A variable that is recognized among all of the procedures on a module sheet is called a "module-level" variable. A module-level variable is available to all of the procedures in that module, but it is not available to procedures in other modules. A module-level variable remains in existence while Visual Basic is running until the module in which it is declared is edited. Module-level variables can be declared with a Dim or Private statement at the top of the module above the first procedure definition.
At the module level, there is no difference between Dim and Private. Note that module-level variables cannot be declared within a procedure.
NOTE: If you use Private instead of Dim for module-level variables, your code may be easier to read (that is, if you use Dim for local variables only, and Private for module-level variables, the scope of a particular variable will be more clear).
In the following example, two variables, A and B, are declared at the module level. These two variables are available to any of the procedures on the module sheet. The third variable, C, which is declared in the Example3 macro, is a local variable and is only available to that procedure.
Note that in Example4, when the macro tries to use the variable C, the message box is empty. The message box is empty because C is a local variable and is not available to Example4, whereas variables A and B are.
Dim A As Integer ' Module-level variable.
Private B As Integer ' Module-level variable.
Sub Example1()
A = 100
B = A + 1
End Sub
Sub Example2()
MsgBox "The value of A is " & A
MsgBox "The value of B is " & B
End Sub
Sub Example3()
Dim C As Integer ' Local variable.
C = A + B
MsgBox "The value of C is " & C
End Sub
Sub Example4()
MsgBox A
' The message box displays the value of A.
MsgBox B
' The message box displays the value of B.
MsgBox C
' The message box displays nothing because C was a local variable.
End Sub
Public variables have the broadest scope of all variables. A public variable is recognized by every module in the active workbook. To make a public variable available to other workbooks, from a new workbook select the workbook containing the public variable in the Available References box of the References dialog box (from a module sheet, click References on the Tools menu).
A public variable, like a module-level variable, is declared at the top of the module, above the first procedure definition. A public variable cannot be declared within a procedure. A public variable is always declared with a "Public" statement. A public variable may be declared in any module sheet.
It is possible for multiple module sheets to have public variables with the same name. To avoid confusion and possible errors, it is a good idea to use unique names or to precede each variable name with a module qualifier (for example, in a module named "Feb_Sales" you may want to precede all public variables with the letters "FS").
To create the macros:
1. Create a new workbook and name it CDSales.xls.
2. In the CDSales.xls workbook, insert a module sheet. Name the module
sheet CDSales.
In Microsoft Excel 97 or Microsoft Excel 98 follow these steps to
insert a new module sheet and name the module sheet:
a. In the CDSales.xls workbook, point to Macro on the Tools menu, and
then click Visual Basic Editor.
b. On the Insert menu, click Module.
c. In Microsoft Excel 97, you can rename a module by activating the
module, clicking to the right of "(Name)" in the Properties window
of the Visual Basic Editor, typing a new module name, and pressing
ENTER.
Public SalesPrice As Integer
Public UnitsSold As Integer
Public CostPerUnit As Integer
Private Markup As Long
Sub CDSales()
Dim X as String
SalesPrice = 12
UnitsSold = 1000
CostPerUnit = 5
Markup = 1.05
X = "yes"
MsgBox "The Gross Profit for CD Sales is $" & (SalesPrice _
* UnitsSold) -(UnitsSold * CostPerUnit * Markup)
' Displays the value of 7000 as the gross profit.
End Sub
5. In the VideoSales.xls workbook, insert a module sheet. Name the module
sheet VideoSales.
In Microsoft Excel 97 or Microsoft Excel 98 follow these steps to
insert a new module sheet and name the module sheet:
a. In the CDSales.xls workbook, point to Macro on the Tools menu, and
then click Visual Basic Editor.
b. On the Insert menu, click Module.
c. In Microsoft Excel 97, you can rename a module by activating the
module, clicking to the right of "(Name)" in the Properties window
of the Visual Basic Editor, typing a new module name, and pressing
ENTER.
Public SalesPrice As Integer
Public UnitsSold As Integer
Public CostPerUnit As Integer
Sub VideoSales()
SalesPrice = CDSales.SalesPrice * 1.05
UnitsSold = CDSales.UnitsSold * 1.456
CostPerUnit = CDSales.CostPerUnit * 1.75
MsgBox "The Projected Gross Profit for video sales is $" & _
(SalesPrice * UnitsSold) - (UnitsSold * CostPerUnit)
' Displays the value of 5824 as the projected gross profit.
End Sub
1. To Create a reference from the workbook VideoSales.xls to CDSales.xls,
select the VideoSales module sheet in VideoSales.xls, and then click
References on the Tools menu.
click the OK button.
1. Rename the project name of the two workbooks so that they are unique
by following these steps:
a. In the Project Explorer pane in the Visual Basic Editor, look at the
projects that are listed. You should see entries similar to the
following:
<VBAProject> (VideoSales.xls)
<VBAProject> (CDSales.xls)
<VBAProject> (Personal.xls)
where <VBAProject> is the name of the project.
b. Click the entry for VideoSales.xls.
c. In the Properties pane, in the box to the right of "(Name)", type a
new, unique project name and press Enter.
Note: Do not use a project name that you use in any other workbook.
d. On the File menu, click Save <bookname>, where <bookname> is the
name of the workbook you modified.
select the VideoSales module sheet in VideoSales.xls, and then click
References on the Tools menu.
specified in step 1c, and then click OK.
Note that the VideoSales macro uses the public variables declared in the CDSales module of CDSales.xls.
The following example tries to use the module-level variable, CDSales.Markup or the local variable CDSales.X in the VideoSales module sheet:
Sub VideoSales2()
MsgBox CDSales.Markup
End Sub
Sub VideoSales3()
MsgBox CDSales.X
End Sub
Member not defined
Compile error:
Method or data member not found
For more information about scope, click the Index tab in Microsoft Excel 7.0 Help, type the following text
scope
For more information about how long the value of a variable is retained, click the Index tab in Microsoft Excel 7.0 Help, type the following text
variables, lifetime
"Visual Basic User's Guide," version 5.0, Chapter 6, "Making Your Variables Available Within Procedures, Modules, or Publicly"
Additional query words: 7.00 5.00 5.00a 5.00c global
Keywords : kbcode kbprg PgmOthr
Version : WINDOWS:5.0,5.0a,5.0c,7.0; MACINTOSH:5.0,98
Platform : MACINTOSH WINDOWS
Issue type : kbinfoLast Reviewed: February 4, 1998