Textbox value needs to be dependant on List box values

[Danyul]

Hi,

I'm sure this should be easy, but I can't solve it at the moment!

I have two list boxes on a form which each hold a count of the no. of entries in a table in the database.

I need a text box (or some other control?) to show the difference between the 2 listbox values.

e.g.> TextBox1.value = ListBox1.value - ListBox2.value

How do i do this?

Regards

Dan

 

[CosmoKramer]

Set the Control Source of the text box to:

=[ListBox1]-[ListBox2]

 

[LonnieJohnson]

I'm not sure what you mean by the listbox holds a count of the entries. Why are you using a listbox. If all you want is the total records in a table you can do this with textboxs using the DCount funtion.

TextBox1: ControlSource value would be...
=DCount("*","Table1&quot
TextBox2: ControlSource value would be...
=DCount("*","Table2&quot
TextBox3: ControlSource value would be...
=[TextBox1]-[TextBox2]

If there is a particular reason you have to use a listbox, then we will need more information.

B-) ljprodev@yahoo.com
ProDev
MS Access Applications

 

[Danyul]

Thank you both,

The DCount method works fine. The reason I was using list boxes was to allow me to use a query to define their contents. (In case I need them to contain a count of a subset of the information etc.).

On exploring the DCount function I find I can include some query criteria that may negate the need for using listboxes.

HOWEVER (!) If I do need to continue using listboxes (for elegance of the solution etc.) I couldn't make Cosmo's solution work, =[ListBox1]-[ListBox2] ,do I need to specify an entry in the listbox (even though it currently only hold one value) ? If so how do I do this?
e.g.
=[ListBox1].entry(x).value - [ListBox2].entry(x).value

Regards

Dan