System.String.LastIndexOfAny Method

Reports the zero-based index position of the last occurrence in this instance of one or more characters specified in a Unicode array. The search starts at a specified character position and proceeds backward toward the beginning of the string.

Syntax

public int LastIndexOfAny (char[] anyOf, int startIndex)

Parameters

anyOf
A Unicode character array containing one or more characters to seek.
startIndex
The search starting position. The search proceeds from startIndex toward the beginning of this instance.

Returns

The index position of the last occurrence in this instance where any character in anyOf was found; -1 if no character in anyOf was found or if the current instance equals string.Empty.

Exceptions

TypeReason
ArgumentNullException anyOf is a null reference.
ArgumentOutOfRangeException startIndex is less than zero or greater than or equal to the length of the current instance.

Remarks

Index numbering starts from zero.

This method begins searching at the startIndex character position of this instance and proceeds backward toward the beginning until either a character in anyOf is found or the first character position has been examined. The search is case-sensitive.

This method performs an ordinal (culture-insensitive) search, where a character is considered equivalent to another character only if their Unicode scalar values are the same. To perform a culture-sensitive search, use the System.Globalization.CompareInfo.LastIndexOf(string, char) method, where a Unicode scalar value representing a precomposed character, such as the ligature "Æ" (U+00C6), might be considered equivalent to any occurrence of the character's components in the correct sequence, such as "AE" (U+0041, U+0045), depending on the culture.

Requirements

Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Assembly Versions: 1.0.5000.0, 2.0.0.0, 4.0.0.0