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# memory and memory recall buttons for a calculator

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I'm very new to programming and to visual basic 6.  I have made a calculator program and the code is as follows:

Option Explicit

Dim bDecimal As Boolean     ' Declares variable to create a flag for the decimal
Dim Op1, Op2                ' Previously input operand.
Dim NumOps As Integer       ' Number of operands.
Dim LastInput               ' Indicate type of last keypress event.
Dim OpFlag                  ' Indicate pending operation.
Dim TempOutput              ' Temporary storage

' Click event procedure for number keys (0-9).
' Append new number to the number in the display.

Private Sub cmdNumber_Click(index As Integer)
If LastInput <> "NUMS" Then
txtOutput.Text = Format(0, ".")
bDecimal = False
End If
If bDecimal Then
txtOutput.Text = txtOutput.Text + cmdNumber(index).Caption
Else
txtOutput.Text = Left(txtOutput.Text, InStr(txtOutput.Text, Format(0, ".")) - 1) + cmdNumber(index).Caption + Format(0, ".")
End If
If LastInput = "NEG" Then txtOutput.Text = "-" & txtOutput.Text
LastInput = "NUMS"
End Sub

' If the immediately preceeding keypress was part of a
' number, increments NumOps. If one operand is present,
' set Op1. If two are present, set Op1 equal to the
' result of the operation on Op1 and the current
' input string, and display the result.

Private Sub cmdOperator_Click(index As Integer)
TempOutput = txtOutput.Text
If LastInput = "NUMS" Then
NumOps = NumOps + 1
End If
Select Case NumOps
Case 0
If cmdOperator(index).Caption = "-" And LastInput <> "NEG" Then
txtOutput.Text = "-" & txtOutput.Text
LastInput = "NEG"
End If
Case 1
Op1 = txtOutput.Text
If cmdOperator(index).Caption = "-" And LastInput <> "NUMS" And OpFlag <> "=" Then
txtOutput.Text = "-"
LastInput = "NEG"
End If
Case 2
Op2 = TempOutput
Select Case OpFlag
Case "+"
Op1 = CDbl(Op1) + CDbl(Op2)
Case "-"
Op1 = CDbl(Op1) - CDbl(Op2)
Case "*"
Op1 = CDbl(Op1) * CDbl(Op2)
Case "/"
If Op2 = 0 Then
MsgBox "Can't divide by zero", 48, "Calculator"
Else
Op1 = CDbl(Op1) / CDbl(Op2)
End If
Case "="
Op1 = CDbl(Op2)
Case "%"
Op1 = CDbl(Op1) * CDbl(Op2)
End Select
txtOutput.Text = Op1
NumOps = 1
End Select
If LastInput <> "NEG" Then
LastInput = "OPS"
OpFlag = cmdOperator(index).Caption
End If
End Sub

' Reset the display and initializes variables.

Private Sub cmdCancel_Click()
txtOutput = Format(0, "0")
Op1 = 0
Op2 = 0
End Sub

Private Sub cmdCancelEntry_Click()
txtOutput.Text = Format(0, "0")
bDecimal = False
LastInput = "CE"
End Sub

' Will check to see if there is already a decimal
' if there is then the decimal is disabled

Private Sub cmdDecimal_Click()
If LastInput = "NEG" Then
txtOutput.Text = Format(0, "-0.")
ElseIf LastInput <> "NUMS" Then
txtOutput.Text = Format(0, "0.")
End If
bDecimal = True
LastInput = "NUMS"
End Sub

Private Sub cmdExit_Click()
End
End Sub

' Calculates the percent of txtOutput

Private Sub cmdPercent_Click()
txtOutput.Text = txtOutput.Text / 100
LastInput = "Ops"
OpFlag = "%"
NumOps = NumOps + 1
bDecimal = True
End Sub

' Initialization routine for the form.
' Set all variables to initial values
' sets the flag to off when the form loads

bDecimal = False
NumOps = 0
LastInput = "NONE"
OpFlag = " "
txtOutput = Format(0, "0")
cmdDecimal.Caption = Format(0, ".")
End Sub

i need to have a memory button and a memory recall button.  Can someone please help me with the code for this.  Thanks in advance.

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## View Solution Only

Commented:
you could use the save setting and getsetting command.

in the save button use
savesetting app.exename,"settings","memory",YourValue

then in the recall button

YourValue=getsetting(app.exename,"settings","memory")

Commented:
The simpler the better if at all possible.  I haven't been taught how to use the savesetting/getsetting command yet.  So I would like to use something that I understand and that would fit easily into my code.  Please and thank you.
Commented:
This one is on us!
(Get your first solution completely free - no credit card required)

Commented:
You could of course just use a public variable which is probably the easiest way.

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