Languages Focus: Empty String Check

An empty string is a zero length string, a string that is equal to null (""), or not assigned. In some languages, you can check if a string is empty by comparing it to an empty string (""). Some languages distinguish between nil and null ("") so checking if the length is 0 is easier.

All these will work for variables unassigned, set to "", or set to Null:

If s&"" = "" Then
  MsgBox ("Quotes with &'' say null is empty")
End If

 
If Len(s&"") = 0 Then
  MsgBox ("Len with &'' says null is empty")
End If

If Len(s&vbNullString) = 0 Then
  MsgBox ("Using vbNullString also works!")
End If