VBA Excel simple Error Handling
There is nothing WRONG in using OERN (On Error Resume Next) provided you understand what you are doing and how it is going to affect your code.
In your case it is perfectly normal to use OERN
Dim shp As Shape
For i = 1 To (a certain number)
On Error Resume Next
Set shp = f_overview.Shapes("btn_" & i)
shp.Delete
On Error GoTo 0
Next
At the same time ensure that you don't do something like
On Error Resume Next
<Your Entire Procedure>
On Error GoTo 0
This will suppress ALL errors. Use proper error handling as shown by Matt
Edit:
Here is another beautiful example on how to use OERN This function checks if a particular worksheet exists or not.
Function DoesWSExist(wsName As String) As Boolean
Dim ws As Worksheet
On Error Resume Next
Set ws = ThisWorkbook.Sheets(wsName)
On Error GoTo 0
If Not ws Is Nothing Then DoesWSExist = True
End Function
If you wish you can also loop through all the sheets to check is the sheet exists or not!
I have found that most of the time, the reccomended fix is to add (on error resume next) before setting the shape, as I get an error saying it does not exist.
NO!
The recommended way to handle runtime errors is not to shove them under the carpet and continue execution as if nothing happened - which is exactly what On Error Resume Next
does.
The simplest way to avoid runtime errors is to check for error conditions, and avoid executing code that results in 100% failure rate, like trying to run a method on an object reference that's Nothing
:
For i = 1 To (a certain number)
Set shp = f_overview.Shapes("btn_" & i)
If Not shp Is Nothing Then shp.Delete
Next
In cases where you can't check for error conditions and must handle errors, the recommended way is to handle them:
Private Sub DoSomething()
On Error GoTo CleanFail
'...code...
CleanExit:
'cleanup code here
Exit Sub
CleanFail:
If Err.Number = 9 Then 'subscript out of range
Err.Clear
Resume Next
Else
MsgBox Err.Description
Resume CleanExit
End If
End Sub