Information.UBound(Array, Int32)Information.UBound(Array, Int32) Method

Definition

Returns the highest available subscript for the indicated dimension of an array.

``public static int UBound (Array Array, int Rank = 1);``
``static member UBound : Array * int -> int``

Parameters

Array
Array Array

Required. Array of any data type. The array in which you want to find the highest possible subscript of a dimension.

Rank
Int32 Int32

Optional. `Integer`. The dimension for which the highest possible subscript is to be returned. Use 1 for the first dimension, 2 for the second, and so on. If `Rank` is omitted, 1 is assumed.

Returns

`Integer`. The highest value the subscript for the specified dimension can contain. If `Array` has only one element, `UBound` returns 0. If `Array` has no elements, for example if it is a zero-length string, `UBound` returns -1.

Exceptions

`Array` is `Nothing`.

`Rank` is less than 1, or `Rank` is greater than the rank of `Array`.

Examples

The following example uses the `UBound` function to determine the highest available subscript for the indicated dimension of an array.

``````Dim highest, bigArray(10, 15, 20), littleArray(6) As Integer
highest = UBound(bigArray, 1)
highest = UBound(bigArray, 3)
highest = UBound(littleArray)
' The three calls to UBound return 10, 20, and 6 respectively.
``````

Remarks

Since array subscripts start at 0, the length of a dimension is greater by one than the highest available subscript for that dimension.

For an array with the following dimensions, `UBound` returns the values in the following table:

``````Dim a(100, 5, 4) As Byte
``````
Call to UBound Return value
`UBound(a, 1)` 100
`UBound(a, 2)` 5
`UBound(a, 3)` 4

You can use `UBound` to determine the total number of elements in an array, but you must adjust the value it returns to account for the fact that the subscripts start at 0. The following example calculates the total size of the array `a` in the preceding example:

``````Dim total As Integer
total = (UBound(A, 1) + 1) * (UBound(A, 2) + 1) * (UBound(A, 3) + 1)
``````

The value calculated for `total` is 3030, which is 101 * 6 * 5.