In Windows Common controls, we have an UpDown control. It can be attached toany textbox. It gives the user the appearance that he or she can control (increment or decrement) the textbox’s text by clicking the Up or Down arrows of the control.

However, the textbox can still have non-numeric text in it, which is notdesirable. This happens because the UpDown control can be bound to any otherproperty of the textbox also, but it hardly is used with any propertyother than the Text property of the textbox. So, if a control can restrict the user from entering data that is not valid, it can be of great help.

The following code does the same. It is to be used inside an Activex Controlproject. Use it for the following:

• Properties like MinValue, MaxValue, Value and Increment—all double datatypes
• Validating the text in the textbox to be within the specifiednumeric region (i.e., >= Min Value, <= Max Value, and above all it should bea valid number)
• Raising a ValueChanged event whenever the value of the control ischanged

To create the control, open a new ActiveX Control project; add a textbox toIt; name it txtCounter; and paste the following code in the code window of theControl:

 Option ExplicitDim dblIncrement As DoubleDim dblMinValue As DoubleDim dblMaxValue As DoubleDim dblValue As DoublePublic Event ValueChanged(NewValue As Double)'Increment propertyPublic Property Let Increment(prmIncrement 
As Double)    dblIncrement = prmIncrementEnd PropertyPublic Property Get Increment() As Double    Increment = dblIncrementEnd Property'MinValue PropertyPublic Property Let MinValue(prmMinValue 
As Double)    If prmMinValue <= dblMaxValue Then        dblMinValue = prmMinValue        Call CorrectValue(dblValue)    End IfEnd PropertyPublic Property Get MinValue() As Double    MinValue = dblMinValueEnd Property'Max value PropertyPublic Property Let MaxValue(prmMaxValue 
As Double)    If prmMaxValue >= dblMinValue Then        dblMaxValue = prmMaxValue        Call CorrectValue(dblValue)    End IfEnd PropertyPublic Property Get MaxValue() As Double    MaxValue = dblMaxValueEnd Property'Value PropertyPublic Property Let value(prmValue As Double)    Call CorrectValue(prmValue)End PropertyPublic Property Get value() As Double    value = dblValueEnd PropertyPrivate Sub txtCounter_Change()    If Not (IsNumeric(txtCounter.Text)) Then        'If the typed in is not numeric, restore it 
to the last value        Beep        txtCounter.Text = CStr(dblValue)    Else        'if typed in value is numeric, correct the 
value and display        CorrectValue (CDbl(txtCounter.Text))    End IfEnd SubPrivate Sub txtCounter_KeyDown(KeyCode 
As Integer, Shift As Integer)    Select Case KeyCode    Case vbKeyUp        Call CorrectValue(CDbl(txtCounter.Text) 
+ dblIncrement)    Case vbKeyDown        Call CorrectValue(CDbl(txtCounter.Text) 
- dblIncrement)    End SelectEnd SubPrivate Sub txtCounter_LostFocus()    CorrectValue (CDbl(txtCounter.Text))End SubPrivate Sub UserControl_ReadProperties(PropBag 
As PropertyBag)    dblMinValue = PropBag.ReadProperty("MinValue", 0)    dblMaxValue = PropBag.ReadProperty("MaxValue", 0)    dblIncrement = PropBag.ReadProperty("Increment", 0)    txtCounter.Text = PropBag.ReadProperty("Value", 0)End SubPrivate Sub UserControl_Resize()    txtCounter.Move 0, 0, UserControl.ScaleWidth, 
UserControl.ScaleHeightEnd SubPrivate Sub UserControl_WriteProperties(PropBag 
As PropertyBag)    PropBag.WriteProperty "MinValue", 
dblMinValue, 0    PropBag.WriteProperty "MaxValue", 
dblMaxValue, 0    PropBag.WriteProperty "Increment", 
dblIncrement, 0    PropBag.WriteProperty "Value", dblValue, 
0End SubPrivate Sub CorrectValue(prmValue As Double)    If prmValue > dblMaxValue Then        'Do not allow the value to increase beyond 
the MaxValue Property        Beep        dblValue = dblMaxValue                txtCounter.Text = CStr(dblValue)        RaiseEvent ValueChanged(dblValue)   'Raise
 the ValueChanged event            ElseIf prmValue < dblMinValue Then        'Do not allow the value to decrease beyond 
the MinValue Property        Beep        dblValue = dblMinValue                txtCounter.Text = CStr(dblValue)        RaiseEvent ValueChanged(dblValue)    
'Raise the ValueChanged event            Else                If prmValue <> dblValue Then            dblValue = prmValue            txtCounter.Text = CStr(dblValue)            RaiseEvent ValueChanged(dblValue)   
'Raise the ValueChangedevent        Else            txtCounter.Text = CStr(dblValue)        End If    End IfEnd Sub