String.LastIndexOf, méthode (String, Int32)

using System;

public class Example
{
   public static void Main()
   {
      int position = 0;
      string s1 = "ani\u00ADmal";
      string s2 = "animal";

      // Find the index of the soft hyphen.
      position = s1.LastIndexOf("m");
      Console.WriteLine("'m' at position {0}", position);
      if (position >= 0)
         Console.WriteLine(s1.LastIndexOf("\u00AD", position));

      position = s2.LastIndexOf("m");
      Console.WriteLine("'m' at position {0}", position);
      if (position >= 0)   
         Console.WriteLine(s2.LastIndexOf("\u00AD", position));

      // Find the index of the soft hyphen followed by "n".
      position = s1.LastIndexOf("m");
      Console.WriteLine("'m' at position {0}", position);
      if (position >= 0)
         Console.WriteLine(s1.LastIndexOf("\u00ADn", position));

      position = s2.LastIndexOf("m");
      Console.WriteLine("'m' at position {0}", position);
      if (position >= 0)   
         Console.WriteLine(s2.LastIndexOf("\u00ADn", position));

      // Find the index of the soft hyphen followed by "m".
      position = s1.LastIndexOf("m");
      Console.WriteLine("'m' at position {0}", position);
      if (position >= 0)
         Console.WriteLine(s1.LastIndexOf("\u00ADm", position));

      position = s2.LastIndexOf("m");
      Console.WriteLine("'m' at position {0}", position);
      if (position >= 0)   
         Console.WriteLine(s2.LastIndexOf("\u00ADm", position));
   }
}
// The example displays the following output:
//       'm' at position 4
//       4
//       'm' at position 3
//       3
//       'm' at position 4
//       1
//       'm' at position 3
//       1
//       'm' at position 4
//       4
//       'm' at position 3
//       3

// Sample for String.LastIndexOf(String, Int32)
using System;

class Sample {
    public static void Main() {

    string br1 = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-";
    string br2 = "0123456789012345678901234567890123456789012345678901234567890123456";
    string str = "Now is the time for all good men to come to the aid of their party.";
    int start;
    int at;

    start = str.Length-1;
    Console.WriteLine("All occurrences of 'he' from position {0} to 0.", start);
    Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str);
    Console.Write("The string 'he' occurs at position(s): ");

    at = 0;
    while((start > -1) && (at > -1))
        {
        at = str.LastIndexOf("he", start);
        if (at > -1) 
            {
            Console.Write("{0} ", at);
            start = at - 1;
            }
        }
    Console.Write("{0}{0}{0}", Environment.NewLine);
    }
}
/*
This example produces the following results:
All occurrences of 'he' from position 66 to 0.
0----+----1----+----2----+----3----+----4----+----5----+----6----+-
0123456789012345678901234567890123456789012345678901234567890123456
Now is the time for all good men to come to the aid of their party.

The string 'he' occurs at position(s): 56 45 8


*/