VBScript Tools for measuring the length of an array and appending values to a Dynamic array

gistfile1.vb

' appends the second argument to the first if the first is an array.
' MUST be a dynamic array! Returns new array.
' Usage:
' Dim myArray()
' myArray = ArrayAppend(myArray, "foo")
Function ArrayAppend( a, o )
  On Error Resume Next
  Err.Clear()
  dim tn, i
  i = 0
  
  tn = TypeName(o)
  
  If isArray(a) Then
	
    i = UBound(a)
	
    If Err.number <> 0 Then
	  Err.Clear() ' We know this causes an error every time.
    Else
      i = i+1
    End If
    
    ReDim Preserve a(i)
	
	If tn <> "Object" Then
		a(i) = o
	Else
		Set a(i) = o
	End If
	
  End If
  
  ArrayAppend = a
  
End Function

' gets the length of an array.
Function ArrayLength( a )
  On Error Resume Next
  dim i: i = 0
  
  i = UBound(a) + 1
  
  ArrayLength = i
  
  Err.Clear()
End Function

Thanks for these. I refactored them to fit a little better with our development style; mostly code reduction, plus an early exit if a is supplied as a non-array for the append function:

' appends the second argument to the first if the first is an array.
' MUST be a dynamic array! Returns new array.
' like so : myArray = ArrayAppend(myArray, "foo")
FUNCTION ArrayAppend(a, o )
    ON ERROR RESUME NEXT
    Err.Clear()
    IF (NOT isArray(a)) THEN
        ArrayAppend = a
        EXIT FUNCTION
    END IF
    DIM tn, i
    i = UBound(a)
    ' We know this causes an error every time.
    IF (Err.number <> 0) THEN Err.Clear() ELSE i = i + 1
    REDIM PRESERVE a(i)
    tn = TYPENAME(o)
    IF (tn <> "Object") THEN a(i) = o ELSE SET a(i) = o
    ArrayAppend = a
END FUNCTION

' gets the length of an array.
FUNCTION ArrayLength( a )
    ON ERROR RESUME NEXT
    DIM i
    i = UBound(a) + 1
    ArrayLength = i
    Err.Clear()
END FUNCTION

I'm glad they were helpful to someone else as well. Thanks for the feedback.

You know after I went through that, I found I couldn't get it to work. Every time I do something like: DIM a() a = ArrayAppend(a, "whatever") I pukes with a type mismatch at runtime. In the meantime I've settled for a hard-coded array with the values I need, but would be good to figure that out. I think it's been about years since the last time I touched anything related to BASIC. :^) Regards, - Sean

…

On Thu, Jun 2, 2011 at 4:43 PM, sholsinger ***@***.*** wrote: I'm glad they were helpful to someone else as well. Thanks for the feedback. ## Reply to this email directly or view it on GitHub: https://gist.github.com/901874

You may also find this one useful: https://gist.github.com/943116

inArray(array, object) ' = index or -1 if not found.

Keenskelly I think I might have figured out what your problem was. I tried to use the ArrayAppend() method to append an array to another array and that doesn't work. It will work on all primitives though -- and might work for Objects. The logic to re-dim an array into a multi-dimensional array is just much more than I'm willing to spend time writing right now. I hate the way VBScript handles arrays.

Me too - I switched to JScript which is so much more sane and familiar and equally supported under the Windows Script Host. I appreciate your taking the time to consider this though. Thanks, - Sean

…

On Thu, Jul 7, 2011 at 11:50 AM, sholsinger ***@***.*** wrote: Keenskelly I think I might have figured out what your problem was. I tried to use the ArrayAppend() method to append an array to another array and that doesn't work. It will work on all primitives though -- and might work for Objects. The logic to re-dim an array into a multi-dimensional array is just much more than I'm willing to spend time writing right now. I hate the way VBScript handles arrays. ## Reply to this email directly or view it on GitHub: https://gist.github.com/901874