List(T).LastIndexOf Method (T, Int32)
Searches for the specified object and returns the zero-based index of the last occurrence within the range of elements in the List(T) that extends from the first element to the specified index.
Assembly: mscorlib (in mscorlib.dll)
- Type: T
The object to locate in the List(T). The value can be a null reference (Nothing in Visual Basic) for reference types.
- Type: System.Int32
The zero-based starting index of the backward search.
The List(T) is searched backward starting at index and ending at the first element.
This method determines equality using the default equality comparer EqualityComparer(T).Default for T, the type of values in the list.
This method performs a linear search; therefore, this method is an O(n) operation, where n is the number of elements from the beginning of the List(T) to index.
The following code example demonstrates all three overloads of the LastIndexOf method. A List(T) 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 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.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.