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Array Index

Documentation

An array index is the number used to access an Array of Variables created using the Dim command.

Description

The following examples illustrate the use of array elements.

If we have an array myArray with elements of 1 to 10, filled with random data:

Index        Data
1              5
2              2
3              6
4              5
5              9
6              1
7              0
8              4
9              5
10             7

One can access each piece of data separately by pointing to the Index of the array element:
Print myArray(5)
Printing the data contained in the fifth element of myArray results in an output of:

To change the contents of an array, use it like any other Variable:
myArray(3) = 0
To print the contents of myArray(3), use the command:
Print myArray(3)
Which results in an output of:

Array elements can be indexed using another Variable. In this example we set all elements in our array to zero:

Dim a As Integer

    For a = 1 To 10

      myArray(a) = 0

    Next a

To change a random array element to a random value:

Dim Index As Integer

    Dim Value As Integer

    index = Int(Rnd(1) * 10) + 1 'This line will simply return a random value between 1 and 10

    Value = Int(Rnd(1) * 10) + 1 'This line will do the same

    myArray(index) = Value

Example

Declare Sub PrintArray()



Dim Numbers(1 To 10) As Integer

Dim Shared OtherNumbers(1 To 10) As Integer

Dim a As Integer



Numbers(1) = 1

Numbers(2) = 2

OtherNumbers(1) = 3

OtherNumbers(2) = 4



PrintArray ()



For a = 1 To 10

 Print Numbers(a)

Next a



Print OtherNumbers(1)

Print OtherNumbers(2)

Print OtherNumbers(3)

Print OtherNumbers(4)

Print OtherNumbers(5)

Print OtherNumbers(6)

Print OtherNumbers(7)

Print OtherNumbers(8)

Print OtherNumbers(9)

Print OtherNumbers(10)



Sub PrintArray ()

 Dim a As Integer

 For a = 1 To 10

   Print otherNumbers(a)

 Next a

End Sub