List(T).IndexOf Method searches for object and returns the zero-based index
Imports System
Imports System.Collections.Generic
Public Class Example
Public Shared Sub Main()
Dim numbers As New List(Of String)
numbers.Add("One")
numbers.Add("Two")
numbers.Add("Three")
numbers.Add("One")
numbers.Add("Four")
numbers.Add("One")
numbers.Add("Five")
Console.WriteLine()
For Each num As String In numbers
Console.WriteLine(num)
Next
Console.WriteLine(numbers.IndexOf("One"))
Console.WriteLine(numbers.IndexOf("One", 3))
Console.WriteLine(numbers.IndexOf("One", 2, 2))
End Sub
End Class