How to use vlookup in vba-excel?

Question

I want to do a vlookup and after finding a value (which will be 1 or 0), I want to put a condition: if it is 1, divide some values of the worksheet by 100.

When executing this code, the error '1004' appears: Unable to get the Vlookup property of the worksheetfunction class

    Sub test()
        Dim inp As Workbook
        Set inp = Workbooks("input_dados.xlsm")
        For i = 2 To 3
            For x = 2 To 112
                Dim NewRange As Range
                Set NewRange = inp.Sheets("Flag_divide").Range(inp.Sheets("Flag_divide").Cells(3, 2), inp.Sheets("Flag_divide").Cells(112, 3))                   
                Dim var_macro As String
                var_macro = inp.Sheets("input").Cells(x + 1, 2).Value                  
                Dim marks As Integer
                marks = Application.WorksheetFunction.VLookup(var_macro, NewRange, 2, False)        
                If marks = 1 Then
                inp.Sheets("input").Cells(x + 1, i + 1).Value = (inp.Sheets("input").Cells(x + 1, i + 1).Value) / 100
                End If
            Next x
        Next i
    End Sub

Answer 1

Common source of error here is that the searched value is not found, and this will throw an error (if you enter the formula on a worksheet, you'll see that result as well).

The preferred way of handling this is to use Application.VLookup rather than WorksheetFunction.VLookup . The former can return an error, the latter will not. This requires either changing your marks to a Variant type, or using an intermediary variable of Variant

Dim marks as Variant
marks = Application.VLookup(var_macro, NewRange, 2, False)
If IsError(marks) Then
    ' Do something, or do nothing...
Else
    If marks = 1 Then
        inp.Sheets("input").Cells(x + 1, i + 1).Value = (inp.Sheets("input").Cells(x + 1, i + 1).Value) / 100
    End If
End If

OR:

Dim marks as Integer ' or String, etc., but you're using Integer
Dim vlook as Variant
vlook = Application.VLookup(var_macro, NewRange, 2, False)
If IsError(vlook) Then
    marks = Empty
Else
    marks = vlook
End If
If marks = 1 Then
    inp.Sheets("input").Cells(x + 1, i + 1).Value = (inp.Sheets("input").Cells(x + 1, i + 1).Value) / 100
End If

Alternatively, you could just double-up on the function call, but I think this is inefficient (and ugly):

Dim marks as Integer ' or String, etc., but you're using Integer
If IsError(Application.VLookup(var_macro, NewRange, 2, False)) Then
    marks = Empty
Else
    marks = Application.VLookup(var_macro, NewRange, 2, False)
End If
If marks = 1 Then
    inp.Sheets("input").Cells(x + 1, i + 1).Value = (inp.Sheets("input").Cells(x + 1, i + 1).Value) / 100
End If

I'd suggest the first approach, for several reasons:

• It seems a bit easier to read, you're not using additional variables that have limited or zero use elsewhere
• On Error Resume Next is clunky, difficult to manage with multiple handlers in a single scope, often mis-used, etc.r
• The Vlookup formula will return whatever is in the cell. This may not always be convertible to String or Integer etc.
• Further, while you've declared marks As String , you're assigning it integer values. This is handled quietly by implicit type conversion, but that's (usually) best to avoid, if possible.

Answer 2

The most frequent situation, in this case, is that your formula didn't find any value. But it can't just assign an Error value to your variable since it's not a cell and it works differently for VBA. Here is how you can bypass this limitation:

On Error Resume Next ' Entering mode <compute it no matter what>
marks = Application.WorksheetFunction.VLookup(var_macro, NewRange, 2, False)
On Error GoTo 0 ' Returning back to a normal error handling
If IsEmpty(marks) Then marks = 0 ' Example on how to handle errors