Calculator within textbox (1 Viewer)

[nhorton79]

Hi All,

Wanting to have a textbox be able to perform calculations prior to saving.

We are often working with square meterage of products in our quantity textbox (txtQty). So would like for users to be able to enter a calculation and have this evaluate prior to updating.

e.g. typing in 10*4/10 would result in 4

I figured that I could maybe put some VBA in the BeforeUpdate event of the textbox using the Eval function.

I've tried entering:

Me.txtQty = Eval(Me.txtQty)

But this doesn't work. Error being the value you entered isn't valid for this field.

Any ideas? Has anyone done anything like this before?

 

[plog]

I have not nor would not do this--I've had users misspell their own names, no way I trust them to input valid calculations. However, I essentially got your code to work.

I made a form with a button and an input, then put this code on the button:

Private Sub ButtonName_Click()

str_Calculation = Eval(Me.InputValue)
MsgBox (str_Calculation)

End Sub

I copied and pasted your calculation and it gave me the right result. Perhaps you can post your code.

 

[MajP]

Calculator

Hi all, Is there an easy way to create a calculator on a form?

www.access-programmers.co.uk

 

[nhorton79]

Sorry if my question was a little vague. Just reread it again.

Users usually just use calculator in windows to get the figure to enter but want to find a way for them to just input directly into the field.

So trusting their input anyway.

I can get it to work by msgbox or printing to immediate window but can’t get it to change the value in the textbox (which is bound).

I suppose I could use a popup calculator as suggested and then populate the textbox from the output of that, just wanted it to be done in the textbox itself but appears there is no event I can use to alter this before saving/updating as beforeupdate event won’t let you change the value.

oh well. Thanks anyway.

 

[June7]

The input has to be to UNBOUND textbox. Then code saves to BOUND textbox.

 

[arnelgp]

Users usually just use calculator in windows to get the figure to enter but want to find a way for them to just input directly into the field.

have you tried the db on post #16 of Calculator | Access World Forums (access-programmers.co.uk)