Hi people, I'm doing a first year university course on VB6.

I need some help with my code. I am getting runtime error 13, type mismatch, its a really simple assignment but because my VB is a student version, I wasn't able to find out what the mismatch is and how to fix it.

This is supposed to just allow you to enter a value, when you click next, it adds the value from whatever was there before to make a new sum. It also shows count or number (how many values have been entered) and also average, the sum divided by count or number. When clear is clicked, it should clear everything.

Code:

Option Explicit
Private Sum As Double
Private Number As Integer
Private Sub cmdClear_Click()
    Sum = 0
    Number = 0
    txtValue.Text = vbNullString
    txtCount.Text = vbNullString
    txtSum.Text = vbNullString
    txtAverage.Text = vbNullString
    txtValue.SetFocus
End Sub

Private Sub cmdNext_Click()
    Dim Value As Double
    Dim Average As Double
    Value = CDbl(txtValue.Text)
    Number = CInt(txtCount.Text)
    Sum = CDbl(txtSum.Text)
    Average = CDbl(txtAverage.Text)
    Number = Number + 1
    Sum = Sum + Value
    Average = Value / Number
End Sub

Private Sub cmdExit_Click()
    Unload Form1
    End
End Sub


Thank you in advance for the help!

Kevin

Hi guys I got the thing to work on my own, but I do have some questions. Here is what I did.

Private Sub cmdNext_Click()
    Dim Value As Double
    Dim Average As Double
    numberCount = numberCount + 1
    txtCount.Text = numberCount
    Value = txtValue.Text
    Sum = Sum + Value
    txtSum.Text = Sum
    Average = Sum / numberCount
    txtAverage.Text = Average
    txtValue.SetFocus
    txtValue = vbNullString
End Sub

My question is what is the difference between declaring the data type of the variable and converting it? i.e. Dim X as Type or Private X As Type between X = CType(txtX.Text)?

Also the way I have done this, does it open it to any errors in data type?

Thanks.

statements like

myVariable = txtbox.Text

will always have problems because you do not know what the user entered in that text box. The right way is to use error handling, so you are always protected, like this:

on error goto errsub
dim myVal as MyType (like integer, double etc)
myval = txtbox.Text
exit sub
errsub:
msgbox "Error reading data: " & err.description

Marco

Thanks Marco. The following code works, so what does setting erorr handling do differently?

Private Sub cmdNext_Click()
    Dim Value As Double
    Dim Average As Double
    numberCount = numberCount + 1
    txtCount.Text = numberCount
    Value = txtValue.Text
    Sum = Sum + Value
    txtSum.Text = Sum
    Average = Sum / numberCount
    txtAverage.Text = Average
    txtValue.SetFocus
    txtValue = vbNullString
End Sub

try to clear txtValue.Text, or enter "a" in it, and see what happens...
The problem is in the line
Value = txtValue.Text
Marco