Variable-length Arrays

[MattyJ]

I have another easy question which seems rather difficult to find the answer to. I would like to define an array to be the size of the length of a recordset that I have taken from my database.

The problem is, when I declare an array like this:

Dim MyArray(intCount) as integer
(or something like that)

It tells me that it wants a constant. I know this is possible in C based languages, but I'm unsure of how it works in VB. Any insight?


Mat

[cafeenman]

you can declare an array one of two ways. Either with a subscript (fixed) or with no subscript (dynamic)

Const MyNum As Long = 12
 
Dim Arr1(MyNum) As String
Dim Arr2(12) As String
Dim Arr3() As String
 
Sub SomeSub()
 
Redim Preserve Arr3(4358345)
 
End Sub

[MattyJ]

Now, would MyNum in your first example be able to be defined like this:

Dim MyInt as Long
MyInt = 12
Const MyNum As Long = MyInt
Dim Arr1(MyNum) As String

Would that work?

And second question, when you define the array dynamically, can you then ReDim it with a variable?

So:

Dim Arr3() As String
Sub SomeSub()
Dim MyNum as Integer
MyNum = 4358345
Redim Preserve Arr3(MyNum)
End Sub

Would either of those two work?

Thanks,


Mat

[cafeenman]

yes
yes

[MattyJ]

Thats exactly what I needed. Thanks very much.


Mat

[cafeenman]

Originally posted by MattyJ
Thats exactly what I needed. Thanks very much.


Mat

If you just use ReDim then the contents of the array are erased. For numbers that means all array elements become 0. For strings they all become an empty string (vbNullString).

If you want to preserve the contents of the array, use ReDim Preserve.