Hello Scott, on my form I have a combo box cmbMgSO4 with values “Yes”; “No” If the user selects Yes, then the text box txtExtra must not be null. The user must provide the dose. For this, I have the validation rule:
IIf([More MgSO4?]=”Yes”, Not IsNull([extra dosage]), IsNull([extra dosage]))
This works until you violate it. Then after you correct the error, the validation text message wouldn’t go away. I understand that it is better to put the validation rule on the form using VB but I need assistance with the below code please. I wrote this code in the AfterUpdate event of [extra dosage] – i.e. the textbox txtExtra but it has bugs. Could you tell me what is wrong with it? Private Sub txtExtra_AfterUpdate()
If [More MgSO4?] = “Yes” Then
If Len([extra dosage].Text & vbNullString) = 0 Then
MsgBox “Please provide the extra dose!”, vbOK + vbExclamation
Else
[extra dosage].Text = Me.txtextra.Text
Len([extra dosage].Text) > 0
End If
Else Len([extra dosage].Text) = 0
End If
End Sub

First, Why use a combobox? I would use a Yes/No field With a default 0 (False). If the user checks that box, use the After Update event of the Checkbox to run code like:

If Me.chkMSGO4 Then
Me.ExtraDosage.SetFocus
End iF

So as soon as the user checks the box, focus is placed in the control. Next I would use the Lost Focus event of ExtraDosage like so:

If IsNull(Me.ExtraDosage) Then
MsgBox "You must enter an extra dosage amount!"
Me.ExtraDosage.SetFocus
End If

So if the user tries to exit the control without entering a value, then they will be returned to the control until they do.

P.S. I moved your post to the Access forum from Other Software, but otherwise you posted fine.

Many thanks Scott. There were certain requirements insisted on (for this form) and using the combo box here is one of them. The application will be used as an analysis tool in the appraisal of Patient Care already administered. The actions and also documentations of the physicians will be taken into consideration. The stake holder wants to know if a decision was made by "Yes" and then the details in the next field. You know what they say, the customer is boss... I used this code and it seems to work. Thanks again:AfterUpdateIf Me.cmbMgSO4 = "Yes" Then Me.txtextra.SetFocusElse Me.cmbHyperTagent.SetFocus End IfLostFocusIf Me.cmbMgSO4 = "Yes" Then If IsNull(Me.txtextra) Then MsgBox "You must enter the extra dose amount!" Me.txtextra.SetFocus End If End If

oh dear. I typed this lengthy response, clicked SUBMIT and lost it! I guess because I was not logged in..

Many thanks Scott. The stakeholder insists on using the combo box as part of the design. The application will be used as an analysis tool in Patient Care appraisal. The decisions and documentation of the physicians is the point of focus. They want to see "Yes" when the form is printed out. You know the saying, the customer is boss...

I used these codes and they seem to be working:

AfterUpdate
If Me.cmbMgSO4 = "Yes" Then
Me.txtextra.SetFocus
Else
Me.cmbHyperTagent.SetFocus
End If


LostFocus
If Me.cmbMgSO4 = "Yes" Then
If IsNull(Me.txtextra) Then
MsgBox "You must enter the extra dose amount!"
Me.txtextra.SetFocus
End If
End If

If they prefer the combobox, as you say that's their choice. I would still be more inclined to use an Option Group than a combobox. But yes, the code will work the same as long as the test is correct. Glad you got it.

P.S. Yes you have to sign in to AMHD first before you can post a response, but it does save what you typed until you sign in.