array variable is empty?

[Guest]

Hi.

Pretend I have an integer array variable that I'm using for somthing,
arIntArray()

There's a loop that goes through and populates the elements of that array,
which are a subset of the columns in the spreadsheet.

If it turns out that there aren't any columns which meet the condition which
populates the array, is there a quick way to determine that the array is
still empty?

Ubound(arIntArray) fails, becuase it's undefined. Is Nothing and Null also
produced errors.

If needed, I can put in a Boolean flag to set if the array gets populated,
but it seems like there is likely another way.

Thanks.
Mark

 

[Guest]

Sub CCC()
Dim arIntArray() As Integer
Dim ub As Long, res As Variant
If Rnd() < 0.5 Then _
ReDim arIntArray(1 To 5)
On Error Resume Next
ub = UBound(arIntArray)
res = Err.Number
On Error GoTo 0
If res <> 0 Then
' not dimmed
MsgBox "Not Dimensioned"
Else
' process the array
MsgBox "Dimensioned"
End If
End Sub

 

[John Coleman]

I don't know if there is anything built in. You can roll your own with
error trapping:

Function IsEmptyArray(A As Variant) As Boolean
Dim test As Long
On Error GoTo must_be_empty
test = UBound(A)
IsEmptyArray = False
Exit Function
must_be_empty:
IsEmptyArray = True
End Function

Sub test()
Dim A() As Long
Dim B() As Long
ReDim B(1 To 2)
B(1) = 5
MsgBox IsEmptyArray(A)
MsgBox IsEmptyArray(B)
End Sub

Hope that helps

-John Coleman

 

[Guest]

thanks, Tom...

so it's basically just seeing if checking the UBound throws an error.

got it.

 

[Guest]

I don't know if there is anything built in. You can roll your own with

error trapping:

something like that is what I was planning to do after seeing Ton's post,
but now that I look at it again, I see that I don't even need to do that.

The loop I have that populates the array by checking the columns, has two
variables, i and j .. i for the columns, and j for the columns that meet the
condition to be added to the array.

j is incremented in the interior of the loop, and if j never gets
incremented, then the array was never populated.

so it turns out that all I have to do is check whether j is still 0.

Thanks.