Stupidly easy question

[alex_read]

BACKGROUND : Teaching brother vb, starting with 3 txtboxes on a form simple calculator example (4 buttons add, minus, divide, multiply). type number into txt1 & txt2, hit one of the 4 buttons, hey presto, total in box3.

PROBLEM :
OK, I use

txt3.text = txt1.text * txt2.text

which works fine with * & /. With the + & - however I get the following:

• ON the -, no entries appear
• On the +, 2 numbers join, not add (I.e.- 1+1=11, 2+2=22)

Now even I know 2+2 is not 22, this just doesn't add up (pun intended there, sorry, had to put it in). Can anyone shed some light on this please?

Thank you!

[mehlar]

I believe the problem is that you are using strings to do math. What you should do is to put your numbers in variables ex. integer, long etc.

lars

[Sforster]

Convert the Text into a numeric data type

either Integer, Single, Double, Byte etc..

txt3.text = CInt(txt1.text) * CInt(txt2.text)

The reason for getting 22 and 11 is because it is concatenating two strings

Hope that helps
Steve

[LAURENS]

Convert ! And use the right operators. Don't use & to add because it will concatenate the strings.
Do something like (I didn't test this, wrote it straight into the reply):

dim dblValue1 as double
dim dblValue2 as double

    if IsNumeric(txt1) then
       dblValue1 = cdbl(txt1)

       if IsNumeric(txt2) then
          dblValue2 = cdbl(txt2)
          
          txt3 = cstr(dblValue1 + dblValue2)
       Else
          msgbox "Non-numeric value
       End
     Else
       msgbox "Non-numeric value
     EndIf

Don't rely on VB to convert values properly. It will often go well, but it will go wrong when you least expect it.

[Joacim Andersson]

Well A + B = AB. When you add text you're concatenatin strings. Textboxes have text in the text property (yeah, no kidding)
What you want to do is to convert the text into number values.

txt3.Text = Val(txt1.Text) + Val(txt2.Text)

Good luck!

[Joacim Andersson]

Wow, I've never seen so many people answering a question at virtually the same time.
Just one comments though;
Don't use CInt if you're not only calculation integers.

[alex_read]

Thank you everyone!