Question

have an access database with a form that has multiple textboxes for production data. I need to do a calculation with a few of the boxes, they are set up as

---

txtA * txtB * txtC = txtD

I need to take the values from each of the boxes and perform this calculation behind the scenes. So I need the value from txtA * txtB * txtC and display the answer to that calculation in txtD. I keep running into issues because of the number of textboxes on my form it will always pick up the wrong data?? HeLP!

Private Sub btnCalculate_Click()
    Dim ctrl As Control
    Dim txt As TextBox

    For Each ctrl In Form.Controls
        If TypeOf ctrl Is TextBox Then
            Set txt = ctrl
            If txt.Name = "txtD" Then
                Set txt = ctrl
                ctrl.SetFocus
                ctrl.Text = calculate
            End If
        End If
    Next ctrl
End Sub

Public Function calculate()
    Dim calc1 As Double        
    calc1 = txtA.Value * txtB.Value * txtC.Value / 144
End Function

I keep getting this error:

Run-time error ‘2185’:
You can’t reference a property or mathod for a control unless the control has the focus.

This is in regards to txtA, txtB, txtC.

Answer 1

Try

txtD = calculate()   

Or

Me!txtD = calculate()

If, for some reason, you want to access a control by its name, do it like this

Dim name As String

name = "txtD"
Me(name) = calculate()

Your calculation function must assign the result to the function name. A potential problem is that you are ignoring types. Of which type is the result of the function? It will be typed as Variant if you don’t specify a type (and a variant can contain about anything). Better

Public Function calculate() As Double
    calculate = CDbl(txtA.Value) * CDbl(txtB.Value) * CDbl(txtC.Value) / 144
End Function

Now, everyone who looks at the function knows what kind of data the textboxes should contain and, more important, what kind of result the function returns.