Not able to read property at runtime - vb6

Question

When I tried to read the "Left property" of a control, it is giving me the error,
"Left cannot be read at run time"
Here is my code,
for each ctrl in me.controls
if ctrl.left > 2490 then
'app logic
end if
next
what is wrong in this code. It worked without error in another computer.
Can anyone tell me what is wrong

Answer 1

You may have a design-time only placeable control on your form like a timer for example, that does not have a run-time left property. You could check the type of control to ensure only TextBox, Label, Button, etc. get checked, or just use an on error resume next:
Check for object type using TypeOf:
Dim ctrl As Control
For Each ctrl In Me.Controls
If TypeOf ctrl Is Timer Then
Else
If ctrl.Left > 2490 Then
'app logic
End If
End If
Next
Check for object type using TypeName:
Dim ctrl As Control
For Each ctrl In Me.Controls
If TypeName(ctrl) = "Timer" Then
Else
If ctrl.Left > 2490 Then
'app logic
End If
End If
Next
Using On Error Resume Next:
Dim ctrl As Control
On Error Resume Next
for each ctrl in me.controls
if ctrl.left > 2490 then
'app logic
end if
Next

Answer 2

If you use the last method, it's important to handle errors inline reraising any unexpected error. Otherwise if you get any different error than the one you're expecting you could have a very tough time finding it. So:
Dim ctrl As Control
On Error Resume Next
for each ctrl in me.controls
if ctrl.left > 2490 then
Select Case Err.Number
Case 0 'No Error, ignore
Case 393 'The error you want to ignore
Err.Clear 'Reset for next iteration
Case Else
On Error Goto 0
Err.Raise Err.Number 'Reraise any unexpected errors
End Select
'app logic
end if
Next
On Error Goto 0