Retrieve the value of a textbox prior to exiting

[Markb384]

Hi guys

I have some code which is designed to limit the entry of data into a text box to integers and half integers only (i.e. 1, 1.5, 2) by assessing the keypress and changing the KeyAscii accordingly. The code is at the end of this post. As I am doing this on a lot of textboxes, I created it as a function, passing the value of the textbox to the function in the form of a string. However, there are some strange occurrences, I think it is to do with the lack of an update of the textbox value when the key is pressed. I was wondering if anyone has any idea on how I can retrieve the value of the textbox using an alternative method which updates more often that using .value?

An example of the strange occurences is that, for instance, I can enter whatever value I like on the initial entry (as presumably the value of the textbox is null), but if I use a decimal place in the entry, I can't override the data without deleting the entry, moving focus away and back, then reentering.

code to call the function on keypress for an example textbox called textA

Private Sub textA_keyPress(KeyAscii As Integer)Dim passedString As String
    passedString = Nz(Me.textA.Value)
    Call force_decimal(Keyascii, passedString)
End Sub

and the code that is called

Public Function force_decimal(Keyascii As Integer, passedString As String)
'a function to force a user to only enter integer or half integer values


    'select the action to take depending on the current textbox value and the key pressed
    Select Case Keyascii
        'for numbers entered, limit to halves and full numbers
        Case Asc("0") To Asc("9")
            If InStr(1, passedString, ".5") > 0 Then
                Keyascii = 0
            ElseIf InStr(1, passedString, ".") > 0 Then
                If Keyascii = Asc("5") Then
                Else: Keyascii = 0
                End If
            End If
        Case 8
        Case Asc(".")
            If InStr(1, passedString, ".") > 0 Then
                Keyascii = 0
            End If
        Case Else
            Keyascii = 0
        End Select
End Function

[ItsMe]

What is an "half integer"?

[Markb384]

Like in the number examples I gave, it's exactly half an integer (e.g. something .5). I wasn't very clear here I suppose, I don't mean integers in the computing sense (i.e. a data type) but more in a mathematical sense.

I think I have solved my issue now though, it appears that using .text rather than .value returns the current state of the textbox rather than the state when focus was last lost.

[ItsMe]

Hmmm.... Never used the Text property with the nz function, seems redundant. If the issue is resolved, it's resolved but, what "state" are you trying to analyze and why are you calling a function using On KeyPress?

[Markb384]

The Nz() was a hangover from when I was referring to the value of the textbox, as when the textbox is initialised on the loaded form it has a null value, which can't logically be compared to something. So I set it to Nz() for this reason. I'm not entirely sure what the text value returns when the field is empty and the value is null, but using Nz() can't harm really.

I thought I explained clearly in my OP. Fundamentally, I want to restrict the keys that a user can press when in a textbox to something that is far more complicated than data validation alone can handle. So I use On KeyPress to catch the key that the user pressed and allow/disallow that key depending on the circumstances. In the end, I only want the textboxes to contain a number which is either an integer or an integer plus a half (i.e. 1, 1.5, 2, 2.5 ad infinitum).

[ItsMe]

untested

Maybe try the on change event handler. At the top of the form's module, declare a couple variables (in the header).
Dim strValue as string
dim intKey as integer

then in the On Change of the textbox.
strValue = ""
intKey = 0
strValue = Nz(Me.textA.Value)
if isnumeric(strValue) then
intKey = Me.textA.OnKeyPress
Call force_decimal(intKey, strValue)
end if