OpenOffice.org BASIC Guide - OpenOffice.org wiki

Determining the Dimensions of Data Fields
Arrays
Functions LBound() and UBound() return respectively the lowest permitted index value and the highest permitted
index value of an array. This is useful when an array has changed its dimensions.
Dim MyArray(10) As Integer
' ... some instructions
Dim n As Integer
n = 47 ' could be the result of a computation
Redim MyArray(n) As Integer
MsgBox(LBound(MyArray)) ' displays : 0
MsgBox(UBound(MyArray)) ' displays : 47
For a multi-dimensional array you need to specify the position (1 to n) of the index you want to know the
permitted lower and upper values:
Dim MyArray(10, 13 to 28) As Integer
MsgBox(LBound(MyArray, 2)) ' displays : 13
MsgBox(UBound(MyArray, 2)) ' displays : 28
Empty arrays
In some cases, especially when dealing with the API, you need to declare an empty array. Such array is declared
without dimension, but may later be filled by an API function or with a Redim statement:
Dim s() As String ' declare an empty array
' --- later in the program ...
Redim s(13) As String
You cannot assign a value to an empty array, since it does not contain any elements.
The "signature" of an empty array is that UBound() returns -1 and LBound() returns 0:
Dim MyArray() As Integer
MsgBox(LBound(MyArray)) ' displays : 0
MsgBox(UBound(MyArray)) ' displays : -1
Some API functions return an array containing elements (indexed from zero) or return an empty array. Use
UBound() to check if the returned array is empty.
Defining values for arrays
Values for the Array fields can be stored like this:
MyArray(0) = "somevalue"
Accessing Arrays
Accessing values in an array works like this:
MsgBox("Value:" & MyArray(0))
Array Creation, value assignment and access example
And example containing all steps that show real array usage:
Sub TestArrayAxess Dim MyArray(3) MyArray(0) = "lala" MsgBox("Value:"
& MyArray(0))End Sub
Chapter 2 · The Language of OpenOffice.org BASIC 19