Need help; trying to figure out why I am getting an error with a leading decimal point in field on userform

[kbishop94]

It only trips an error when I "tab" into the field (upon which it turns blue) and then if a decimal point is entered as the first character I get:

"Run-time error '13:'
Type mismatch"

If I use the backspace key to remove any numerals that might be in the field, and then hit decimal (but its still the first character entered) then I do not get an error and it accepts the leading decimal.. (???)
(the RED code is where the error is highlighted)

[COLOR=#008000]' CODE FOR THE FIRST TEXT BOX FOR ALLOWING A DECIMAL POINT AS THE LEADING CHARACTER:[/COLOR]
Private Sub txtCostProd1_KeyPress(ByVal KeyAscii As MSForms.ReturnInteger)
If Not (KeyAscii > 47 And KeyAscii < 59) Then
  If KeyAscii = 46 And Len(txtCostProd1.Text) = 0 Then
    txtCostProd1.Text = "0"
  ElseIf Not (KeyAscii = 46 And InStr(txtCostProd1.Text, ".") = 0) Then
Beep:     KeyAscii = 0
  End If
End If
End Sub

[COLOR=#008000]' CODE FOR THE SECOND TEXT BOX FOR ALLOWING A DECIMAL POINT AS THE LEADING CHARACTER:[/COLOR]
Private Sub txtCostShip1_KeyPress(ByVal KeyAscii As MSForms.ReturnInteger)
If Not (KeyAscii > 47 And KeyAscii < 59) Then
  If KeyAscii = 46 And Len(txtCostShip1.Text) = 0 Then
    txtCostShip1.Text = "0"
  ElseIf Not (KeyAscii = 46 And InStr(txtCostShip1.Text, ".") = 0) Then
Beep:     KeyAscii = 0
  End If
End If
End Sub

Private Sub txtCostProd1_Change()
    TextBoxesSum
End Sub

Private Sub txtCostShip1_Change()
    TextBoxesSum
End Sub

Private Sub TextBoxesSum()
    Dim Total As Double
    Total = 0
        
    If Len(txtCostProd1.Value) > 0 Then Total = [COLOR=#ff0000][B]Total + CDbl(txtCostProd1.Value)[/B][/COLOR]
    If Len(txtCostShip1.Value) > 0 Then Total = Total + CDbl(txtCostShip1.Value)
    
    txtCost1.Value = Total

End Sub

Here is a screenshot of my form (part of it) showing the textboxes as mentioned in the above code:

Everything else in the code functions as intended (it sums up the totals just as it should), but I cant understand why it doesnt like it when a decimal point is entered as the first character, and only when the number that is present in the textbox is BLUE(as in highlighted) If I backspace over the character(s) that are in there, then hit the decimal point, it accepts it. (?) very strange....

 

[JLGWhiz]

I'm guessing since you are making the entry in a text box and the variable is delcared as Double, that the compiler is somehow picking that decimal up as txt and throwing the error 13. Try starting your entry with a zero and see if it still throws the error.

 

[Rick Rothstein]

The problem is in this part of your code line...

CDbl(txtCostProd1.Value)

When you enter a decimal point as the first character in the textbox, that part of your code line becomes this..

CDbl(".")

A decimal point by itself (which could be a "period" of course) cannot be converted to a Double as it is not a number. If you change that part of your code to this, I think it will work for you...

CDbl("0" & txtCostProd1.Value)

Alternately, you should be able to use the Val function instead of the CDbl function...

Val(txtCostProd1.Value)

 

[kbishop94]

Thank you, Rick! You came through again for me. Much appreciation to you kind sir.

The problem is in this part of your code line...

CDbl(txtCostProd1.Value)

When you enter a decimal point as the first character in the textbox, that part of your code line becomes this..

CDbl(".")

A decimal point by itself (which could be a "period" of course) cannot be converted to a Double as it is not a number. If you change that part of your code to this, I think it will work for you...

CDbl("0" & txtCostProd1.Value)

Alternately, you should be able to use the Val function instead of the CDbl function...

Val(txtCostProd1.Value)