keep getting error

[lipin]

I have a combobox and 3 textboxes. THe 3 textboxes are populated depending on the number in the combobox. I keep getting the INVALID USE OF NULL error when the combo box receives the focus and then the user tabs to the next box without entering a number. But I want the user to be able to do this. Here is my code:

Private Sub Employee_Exit(Cancel As Integer)
If IsNull(Employee) Then Exit Sub

Dim strName As String
Dim strShift As String
Dim strDept As String

strName = [Employee].Column(1) <---error is here when I
txtname = strName debug

strShift = [Employee].Column(2)
txtshift2 = strShift

strDept = [Employee].Column(3)
txtjob = strDept
End Sub

I thought the If isnull at the beginning would eliminate error but it doesn't. How can I avoid NULL error?

 

[sambo]

Try using the After Update event instead of the Exit Event. This way it only changes the text boxes when the Combo Box has actually been altered.

Also, Here is a good replacement for IsNull, It works for more than just strings, it also checks Type Number, Boolean, Currency, etc...

Sample Call:

If IsNothing(Me.ComboBox) Then Exit Sub

Function IsNothing(varToTest As Variant) As Integer
' Tests for a "logical" nothing based on data type
' Empty and Null = Nothing
' Number = 0 is Nothing
' Zero length string is Nothing
' Date/Time is never Nothing

IsNothing = True

Select Case VarType(varToTest)
Case vbEmpty
Exit Function
Case vbNull
Exit Function
Case vbBoolean
If varToTest Then IsNothing = False
Case vbByte, vbInteger, vbLong, vbSingle, vbDouble, vbCurrency
If varToTest <> 0 Then IsNothing = False
Case vbDate
IsNothing = False
Case vbString
If (Len(varToTest) <> 0 And varToTest <> " ") Then IsNothing = False
End Select

End Function