List.LastIndexOf Method

Definition

Overloads

Examples

The following example demonstrates all three overloads of the LastIndexOf method. A List of strings is created, with one entry that appears twice, at index location 0 and index location 5. The LastIndexOf(T) method overload searches the entire list from the end, and finds the second occurrence of the string. The LastIndexOf(T, Int32) method overload is used to search the list backward beginning with index location 3 and continuing to the beginning of the list, so it finds the first occurrence of the string in the list. Finally, the LastIndexOf(T, Int32, Int32) method overload is used to search a range of four entries, beginning at index location 4 and extending backward (that is, it searches the items at locations 4, 3, 2, and 1); this search returns -1 because there are no instances of the search string in that range.

using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        List dinosaurs = new List();

        dinosaurs.Add("Tyrannosaurus");
        dinosaurs.Add("Amargasaurus");
        dinosaurs.Add("Mamenchisaurus");
        dinosaurs.Add("Brachiosaurus");
        dinosaurs.Add("Deinonychus");
        dinosaurs.Add("Tyrannosaurus");
        dinosaurs.Add("Compsognathus");

        Console.WriteLine();
        foreach(string dinosaur in dinosaurs)
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\nLastIndexOf(\"Tyrannosaurus\"): {0}",
            dinosaurs.LastIndexOf("Tyrannosaurus"));

        Console.WriteLine("\nLastIndexOf(\"Tyrannosaurus\", 3): {0}",
            dinosaurs.LastIndexOf("Tyrannosaurus", 3));

        Console.WriteLine("\nLastIndexOf(\"Tyrannosaurus\", 4, 4): {0}",
            dinosaurs.LastIndexOf("Tyrannosaurus", 4, 4));
    }
}

/* This code example produces the following output:

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Brachiosaurus
Deinonychus
Tyrannosaurus
Compsognathus

LastIndexOf("Tyrannosaurus"): 5

LastIndexOf("Tyrannosaurus", 3): 0

LastIndexOf("Tyrannosaurus", 4, 4): -1
 */

Imports System.Collections.Generic

Public Class Example

    Public Shared Sub Main()

        Dim dinosaurs As New List(Of String)

        dinosaurs.Add("Tyrannosaurus")
        dinosaurs.Add("Amargasaurus")
        dinosaurs.Add("Mamenchisaurus")
        dinosaurs.Add("Brachiosaurus")
        dinosaurs.Add("Deinonychus")
        dinosaurs.Add("Tyrannosaurus")
        dinosaurs.Add("Compsognathus")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & _
            "LastIndexOf(""Tyrannosaurus""): {0}", _
            dinosaurs.LastIndexOf("Tyrannosaurus"))

        Console.WriteLine(vbLf & _
            "LastIndexOf(""Tyrannosaurus"", 3): {0}", _
            dinosaurs.LastIndexOf("Tyrannosaurus", 3))

        Console.WriteLine(vbLf & _
            "LastIndexOf(""Tyrannosaurus"", 4, 4): {0}", _
            dinosaurs.LastIndexOf("Tyrannosaurus", 4, 4))

    End Sub
End Class

' This code example produces the following output:
'
'Tyrannosaurus
'Amargasaurus
'Mamenchisaurus
'Brachiosaurus
'Deinonychus
'Tyrannosaurus
'Compsognathus
'
'LastIndexOf("Tyrannosaurus"): 5
'
'LastIndexOf("Tyrannosaurus", 3): 0
'
'LastIndexOf("Tyrannosaurus", 4, 4): -1

public:
 int LastIndexOf(T item);

public int LastIndexOf(T item);

member this.LastIndexOf : 'T -> int

Public Function LastIndexOf (item As T) As Integer

public:
 int LastIndexOf(T item, int index);

public int LastIndexOf(T item, int index);

member this.LastIndexOf : 'T * int -> int

Public Function LastIndexOf (item As T, index As Integer) As Integer

public:
 int LastIndexOf(T item, int index, int count);

public int LastIndexOf(T item, int index, int count);

member this.LastIndexOf : 'T * int * int -> int

Public Function LastIndexOf (item As T, index As Integer, count As Integer) As Integer