LastIndexOf Method (Object, Int32, Int32)
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ArrayList.LastIndexOf Method (Object, Int32, Int32)

 

Searches for the specified Object and returns the zero-based index of the last occurrence within the range of elements in the ArrayList that contains the specified number of elements and ends at the specified index.

Namespace:   System.Collections
Assembly:  mscorlib (in mscorlib.dll)

abstract LastIndexOf : 
        value:Object *
        startIndex:int *
        count:int -> int
override LastIndexOf : 
        value:Object *
        startIndex:int *
        count:int -> int

Parameters

value
Type: System.Object

The Object to locate in the ArrayList. The value can be null.

startIndex
Type: System.Int32

The zero-based starting index of the backward search.

count
Type: System.Int32

The number of elements in the section to search.

Return Value

Type: System.Int32

The zero-based index of the last occurrence of value within the range of elements in the ArrayList that contains count number of elements and ends at startIndex, if found; otherwise, -1.

Exception Condition
ArgumentOutOfRangeException

startIndex is outside the range of valid indexes for the ArrayList.

-or-

count is less than zero.

-or-

startIndex and count do not specify a valid section in the ArrayList.

The ArrayList is searched backward starting at startIndex and ending at startIndex minus count plus 1, if count is greater than 0.

This method performs a linear search; therefore, this method is an O(n) operation, where n is count.

This method determines equality by calling Object.Equals.

Starting with the .NET Framework 2.0, this method uses the collection’s objects’ Equals and CompareTo methods on item to determine whether item exists. In the earlier versions of the .NET Framework, this determination was made by using the Equals and CompareTo methods of the item parameter on the objects in the collection.

The following code example shows how to determine the index of the last occurrence of a specified element. Note that LastIndexOf is a backward search; therefore, count must be less than or equal to startIndex + 1.

No code example is currently available or this language may not be supported.

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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