Lose focus at wrong time

[newUser1234]

Hello i have a data validation check upon lost focus for a vb textbox:

Private Sub fromText_LostFocus()
 
If IsNull(fromText.Text) = True Then
    MsgBox StrMsg, vbExclamation   
 
End If
 
End Sub
 

It will check if its null, if so it'll display an error message. But then it will lose focus, i want it to stay in that text box until the user enters something.

[pureenhanoi]

Hello i have a data validation check upon lost focus for a vb textbox:

Private Sub fromText_LostFocus()
 
If IsNull(fromText.Text) = True Then
    MsgBox StrMsg, vbExclamation   
 
End If
 
End Sub
 

It will check if its null, if so it'll display an error message. But then it will lose focus, i want it to stay in that text box until the user enters something.

Using Validate event instead of LostFocus.
If the value still null, set the Cancel = True to keep the focus

[Killer42]

Using Validate event instead of LostFocus.
If the value still null, set the Cancel = True to keep the focus

The Validate event has an added advantage.
Let's say you have a Cancel button or something. Generally, the user would not expect to have to enter a value in your field, just so they can exit by hitting Cancel. If you do the check in LostFocus, it will always complain about the null, even if the user is just trying to exit. But if you do it in Validate, you can skip it by setting the Cancel button's CausesValidation property to False. This simply means "don't bother triggering validation on the control we left, before entering this one".