C# String LastIndexOfAny(Char[], Int32, Int32)

Description

String LastIndexOfAny(Char[], Int32, Int32) 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 for a specified number of character positions.

Syntax

String.LastIndexOfAny(Char[], Int32, Int32) has the following syntax.

public int LastIndexOfAny(
  char[] anyOf,//  ww  w  .j  a v  a  2s.c  om
  int startIndex,
  int count
)

Parameters

String.LastIndexOfAny(Char[], Int32, Int32) has the following 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.
• count - The number of character positions to examine.

Returns

String.LastIndexOfAny(Char[], Int32, Int32) method 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.

Example

Sample for String.LastIndexOfAny(Char[], Int32, Int32)

/*w  ww.  j a v  a  2 s .c o m*/
using System;

class Sample {
    public static void Main() {
    string str = "this is a test.";
    string target = "is";
    char[] anyOf = target.ToCharArray();
    int start = ((str.Length-1)*2)/3;
    int count = (str.Length-1)/3;

    int at = str.LastIndexOfAny(anyOf, start, count);
    if (at > -1) 
        Console.Write(at);
    else
        Console.Write("(not found)");
    }
}

The code above generates the following result.