counting array elements (vb6)

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Hello all

I have an array with soem of it being empty after the data gets put into it, how can I count the non-empty elements in my array.

Thanks

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Use something like

Dim lngCount As Long
Dim lngIndex As Long
lngCount = 0
For lngIndex = LBound(arrMyArray) To UBound(arrArray)
If Not IsEmpty(arrMyarray(lngIndex)) Then lngCount = lngCount + 1
Next lngIndex
MsgBox lngCount

where arrMyArray is the name of the array (I have assumed it to be one-dimensional)

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IsEmpty works only for Variants.

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That is correct. I had assumed that the poster was working with Variants, but it might be useful to explain this.

Each array element is assigned a default value when the array is created.
For an array of Variants, this default value is Empty.
For an array of Integers or another numeric type, it is 0.
For an array of Strings, it is “”.
For an array of Booleans, it is False.

If you have an array of Integers or Strings or Booleans etc., you really can’t say that an element is “empty”. You can’t distinguish between an element that is 0 because it was never assigned a value by the user/programmer, and an element that is 0 because the user/programmer set it to 0 explicitly.

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It may of interest to note how differently VB and VB .NET handle “Nothing”.
The following VB 6 code is invalid, but it imports “correctly” into VB .NET.

Option Explicit
Private Sub Main()
    TestNothing
End Sub
Private Sub TestNothing()
    Dim intIndex As Integer
    intIndex = -1
    intIndex = Nothing
    Debug.Print intIndex
End Sub

In VB 6, the code is incorrect because you cannot set an Integer variable to Nothing.

When converted to VB .NET, you can use such an assignmenbty, but Nothing, in VB .NET, means the default value of 0, so you still cannot detect a variable that has not been assigned.

The VB .NET code is:

Option Strict Off
Option Explicit On
Module modMiscellaneous
	Public Sub Main()
		TestNothing()
	End Sub
	Private Sub TestNothing()
		Dim intIndex As Short
		intIndex = -1
		intIndex = Nothing
		System.Diagnostics.Debug.WriteLine(intIndex)
	End Sub
End Module

NOTE: Is there a bug in the use of the pre tag in the lounge, or did I not use the pre tag correctly? There definitely is a problem with extra blank lines being inserted after the each /pre tag.

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The [Pre] and [Quote] tags both insert blank lines before and after to set the enclosed text off from the rest of the message. Just don’t stick any additional blank lines in and it will be fine. That’s the way they’ve worked from the beginning.

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