Automatically resest variable values = 0 after runtime

[RyanH]

I have about 40 variables at the top of a Userforms Declaration section. I
do this because I need the variables calculated in one procedure and made
available to another procedure when they are all done being calulated.

The problem is I currently have to write code to reset all the variables
back to 0 before they are recalculated. If there a way to declare the
variable (DataType Single) = 0 at the beginning of runtime. For example:

Option Explicit

Dim var1 As Single = 0
Dim var2 As Single = 0

Private Sub CalculateVariables()

' code to calculate var1 & var2

End Sub

Private Sub UseVariables

' code to use var1 & var2

End Sub

After runtime var1 & var2 are reset to 0

 

[Charlie]

Why exactly do you need to reset ALL of them? In a situation where a value
is used to recalculate itself, such as

n = n + 1

then, yes, you need to reset. But for most calcs

a = b + c

you would not need to reset "a" first. And I presume "b" and "c" would be
obtained from some external source, and THEY would not need to be reset first
either.

Post some code.

 

[JLGWhiz]

Once the procedure executes End Sub all variables are emptied anyhow. They
do not retain their values for a second run. Even if the variables are
public and your procedure calculates their value at each run, they would not
have to be reset to zero, unless as Charlie pointed out, you are adding the
existing value to something. In that case you could use an If statement to
say if it is greater than zero then make it zero.

 

[RyanH]

I realize what you are saying Charlie and JLGWhiz, and I agree. I apologize
for not posting code. I basically shorted my code to better explain my
question.

This code is placed in a Userform Module. My executed code is fired when I
click the command button on my UserForm.

My problem is when I click the command button lets say CheckBox 1 & 2 =
True. Thus, Var1 = 100, Var2 = 200, Var3 = 300, Var4 = 400 and the Message
Box is shown 4 times (Note: UserForm is still open). If I set CheckBox1 =
True and CheckBox2 = False and then click my command button a second time I
should only see the MsgBox 2 times, right? Wrong, the Message Box is shown 4
times again, because I delared my variables at the top in the Declarations
section, which holds the variable value until the Userfrom is Unloaded.

So I was wanting to know if there is a way to automatically reset the
variables = 0 each time the command button is clicked (Such as Dim var1 As
Single = 0). I currently have code that uses the Array and a For Each...Loop
to set the variables = 0, which I did not display below. I just figured
there may be an easier way.

Option Explicit

Dim var1 As Single
Dim var2 As Single
Dim var3 As Single
Dim var4 As Single

Private Sub CommandButton1_Click()

Call UseVariables

End Sub

Private Sub UseVariables()

Dim myVariables As Variant
Dim myVar As Variant

Call CalculateVariables

myVariables = Array(var1, var2, var3, var4)

For Each myVar In myVariables
If myVar <> 0 Then
MsgBox "Do Something"
End If
Next myVar

End Sub

Private Sub CalculateVariables()

If CheckBox1 = True Then
var1 = 100
var2 = 200
End If

If CheckBox2 = True Then
var3 = 300
var4 = 400
End If

End Sub

 

[Charlie]

I hate to be the bearer of bad news but this is how I do it (no automatic
reset):

If CheckBox1 Then
var1 = 100
var2 = 200
Else
var1 = 0
var2 = 0
End If

 

[Rick Rothstein \(MVP - VB\)]

Change your CalculateVariable subroutine to the following and the variables
will set themselves to the correct value or reset themselves to 0 depending
on the True or False status of the various CheckBoxes...

Private Sub CalculateVariables()

var1 = -100 * CheckBox1.Value
var2 = -200 * CheckBox1.Value

var3 = -300 * CheckBox2.Value
var4 = -400 * CheckBox2.Value

End Sub

Note the minus sign in front of the numbers... that is very important. What
is going on here is the numerical value is being multiplied by either True
or False (depending on if the CheckBox is checked or not) which, in VB,
is -1 (minus 1) for True and 0 for False. Hence, using var1 as an example,
the multiplication automatically sets the value to -100 (minus 100) times
either -1 (minus 1) if the CheckBox is checked (its Value property would be
True) or time 0 if it is not checked (its Value property would be False).
Since a minus times a minus is a plus, var1 is set to either 100 or 0
automatically.

Rick

 

[Rick Rothstein \(MVP - VB\)]

By the way, you can use the same technique on String variable too. For
example...

strVar1 = Left("Some text", -9 * CheckBox1.Value)

where the 9 is the length of the text in quote marks. Again, note the minus
sign in front of the length of the text. This statement will either assign
the full string value or the empty string ("") to strVar1 depending on if
the CheckBox is checked or not.

Rick

 

[Rick Rothstein \(MVP - VB\)]

One final thought on this method... if you had a lot of variables to set for
any given CheckBox, you could use a With/End With block to avoid having to
type in the CheckBox name each time. For example....

With CheckBox1
var1 = -100 * .Value
var2 = -200 * .Value
etc.
End With

Rick

 

[RyanH]

Thanks for the help Rick. I actually was using the code I posted as an
example. Your method would help for some of the controls on my Userform but
not all. Your method did give me a good idea though to use in the future.


--
Cheers,
Ryan

One final thought on this method... if you had a lot of variables to set for
any given CheckBox, you could use a With/End With block to avoid having to
type in the CheckBox name each time. For example....

With CheckBox1
var1 = -100 * .Value
var2 = -200 * .Value
etc.
End With

Rick

 

[Rick Rothstein \(MVP - VB\)]

What are the controls you have that it would not be helpful for (there is
probably another way to do it for them)?

Note: It's very hard to give you advice for something you don't tell us
about.<g>

Rick

Thanks for the help Rick. I actually was using the code I posted as an
example. Your method would help for some of the controls on my Userform
but
not all. Your method did give me a good idea though to use in the future.

 

[RyanH]

Rick,

The following code is an example of what my actual code is (my actual code
is too lengthy to post). myArray will always contain 4 variables. I need to
reset each variable in myArray equal to 0 each time Sub Test() is called. As
you can see I have to declare the variables in the Declarations section to
make them available to both procedures. By doing this unwanted text is
copied from Sheet1 to Sheet2.

For example, in my UserForm say the user fires the Test_Click Event and
CheckBox1 = True and ComboBox.ListIndex = 1, thus var1=100, var2=0, var3=300,
var4=0 and the UserFrom remains Loaded. So far so good! The problem happens
when the user may fire the Test_Click Event again when CheckBox1 = False and
ComboBox.ListIndex = 3, thus var1=100, var2=200, var3=300, var4=400. This is
no good, because now all four variables have data other than = 0. The
variables should show like this: var1=0, var2=200, var3=0, var4=400.

So how do I reset the variables values without destroying myArray? I don't
think I could use Erase or ReDim, because this would destroy the Array,
right? I thought about just looping thru myArray and make each variable =
Empty, but I figured there would be a more efficient way. I hope this is
clear.


Option Explicit

Dim var1 As Single
Dim var2 As Single
Dim var3 As Single
Dim var4 As Single

Private Sub cmbTest_Click()

Dim myArray As Variant

' array of row numbers determined by procedure cmbCalculate_Click
myArray = Array(var1, var2, var3, var4)

' calculate variables in myArray
Call cmbCalculate_Click

' adds text from Sheet1 to Sheet2
InputRow = 6
For i = LBound(myArray) To UBound(myArray)
If Not myArray(i) = 0 Then
Sheets("Sheet1").Range("A" & InputRow & "" &
InputRow).Value = _
Sheets("Sheet2").Range("A" & myArray(i) & "" &
myArray(i)).Value
InputRow = InputRow + 2
End If
Next i

End Sub

Private cmbCalculate_Click()

If CheckBox1 = True Then
var1 = 100
Else
var2 = 200
End If

If ComboBox.ListIndex = 1 Then
var3 = 300
Else
var4 = 400
End If

End Sub

 

[Mike Missakian]

Have you tried moving the variables and the array to a class? Make the
array static and make the variables public (or use properties - for to
shortcut it I used public properties). Then everytime you "new" up the
class the variables will be reset but the array will stay around as
static - then pass that new'd up class to your sub-routines.

For example:
Class code: (shortened for simplicity)
Public Class TestClass

Public Var1 As Integer = 0

Public Shared myArray(4) As String

End Class


Form code: (again shortened for simplicity)
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load

myArray(0) = DateTime.Now.ToString("fffff")
Thread.Sleep(2)

myArray(1) = DateTime.Now.ToString("fffff")
Thread.Sleep(2)

myArray(2) = DateTime.Now.ToString("fffff")
Thread.Sleep(2)

myArray(3) = DateTime.Now.ToString("fffff")
Thread.Sleep(2)

End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button1.Click

Dim tmpTestClass As New TestClass

tmpTestClass.Var1 = CType(DateTime.Now.ToString("fffff"), Int32)

MessageBox.Show(String.Format("Class member value: {0}, Static
array at 0={1}", tmpTestClass.Var1.ToString(), myArray(0).ToString()))

End Sub


When this gets run and the button is clicked - the array remains the
same but the "var1" is always new.

Is this what you're after?

-Mike

 

[Rick Rothstein \(MVP - VB\)]

I might be missing something, but I am having trouble seeing why my earlier
suggestion...

With CheckBox1
var1 = -100 * .Value
var2 = -200 * .Value
etc.
End With

is not useful... just put it in each of the Click events for each of your
CheckBoxes (or better yet, make it a subroutine and call that subroutine
from the CheckBox Click events.

Rick