Dim txt As String
Dim blank As String
blank = ""
:
If Len(txt) = 0 Then ...
If txt = vbNullString Then ...
If txt = "" Then ...
If txt = blank Then ... 'The test Len(txt) = 0 is roughly 20 percent faster than
'the others.
(instringnull.html)- by Paolo Puglisi - Modifica del 25/3/2019