using System;
namespace PointerDemo
{
 public class PointerDemo
 {
 public static void Main()
 {
  string s = "Hello Csharp!"; // 原字符串
  Console.Write("the original string: ");
  Console.WriteLine("{0}\r\n", s);
  char[] b = new char[100];
  s.CopyTo(0,b,0,13);
  Console.Write("the encoded string: ");
  // 使用不安全代码
  unsafe
  {
  // 加密过程
  // 将字符串指针p指向字符数组b，并将参数p传给函数
  fixed(char *p = b) NEncodeDecode(p);
  }
  for(int i = 0; i < 13; i++)
  Console.Write(b[i]);
  Console.WriteLine("\r\n");
   Console.Write("the decoded string: ");
  unsafe
  {
  // 解密过程
  fixed(char *p = b)NEncodeDecode(p);
  }
  for(int i = 0; i < 20; i++)
  Console.Write(b[i]);
  int t = 2;
  t = t^5;
  Console.WriteLine(t);
  Console.WriteLine();
 }
 // 对给定字符串进行加密处理
 unsafe public static void NEncodeDecode(char *s)
 {
  int w;
  for(int y = 0; y < 13; y++)
  {
  w = (int) *(s + y);
  w = w^5; // 异或运算
  *(s + y) = (char)w;
  }
 }
 }
}