Name

Array.IndexOf Method

Class

System.Array

Syntax

Array.IndexOf(Array, Value[, startIndex[, count]])
Array

Use: Required

Data Type: Any array

The array to be searched

Value

Use: Required

Data Type: Any

The object that is searched for

startIndex

Use: Optional

Data Type: Integer

The index at which to start the search

count

Use: Optional

Data Type: Integer

The number of items to search

Return Value

The index of the first occurrence of Value in Array, or -1

Description

Returns an Integer representing the index of the first occurrence of object in Array

Rules at a Glance

  • Array must be a one-dimensional array.

  • By default, the IndexOf method searches for Value from the beginning to the end of Array.

  • If startIndex is provided without count, IndexOf searches from startIndex to the last element of Array.

  • If both startIndex and count are provided, the method searches count elements starting at startIndex. In other words, it searches from array(startIndex) to array(startIndex + count - 1).

  • If startIndex is present and is outside of the range of the elements in array, the method returns -1.

  • If count is present and startIndex + count - 1 exceeds the total number of elements in array, the method call generates an ArgumentOutOfRangeException exception.

Example

The following code searches for a value in an Integer array:

Dim i As Integer
Dim a(99999) As Integer
For i = 0 To 99999
    a(i) = CInt(Rnd(  ) * 100000)
Next
MsgBox(Array.IndexOf(a, 36500))

You can also specify the starting index for the search, as well as ...

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