CRC32算法C#中的实现

代码如下：

 using System;
 using System.Collections.Generic;
 using System.Text;
 using System.IO;

 namespace GetCRC32
 {
     class CRC32Cls
     {
         protected ulong[] Crc32Table;
         //生成CRC32码表
         public void GetCRC32Table()
         {
             ulong Crc;
             Crc32Table = new ulong[];
             int i,j;
             for(i = ;i < ; i++)
             {
                 Crc = (ulong)i;
                 for (j = ; j > ; j--)
                 {
                     if ((Crc & ) == )
                         Crc = (Crc >> ) ^ 0xEDB88320;
                     else
                         Crc >>= ;
                 }
                 Crc32Table[i] = Crc;
             }
         }

         //获取字符串的CRC32校验值
         public ulong GetCRC32Str(string sInputString)
         {
             //生成码表
             GetCRC32Table();
             byte[] buffer = System.Text.ASCIIEncoding.ASCII.GetBytes(sInputString);
             ulong value = 0xffffffff;
             int len = buffer.Length;
             for (int i = ; i < len; i++)
             {
                 value = (value >> ) ^ Crc32Table[(value & 0xFF)^ buffer[i]];
             }
             return value ^ 0xffffffff;
         }
     }
 }

调用代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace GetCRC32
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            CRC32Cls CRC = new CRC32Cls();
            textBox2.Text = String.Format("{0:X8}", CRC.GetCRC32Str(textBox1.Text));
        }

        private void button2_Click(object sender, EventArgs e)
        {

        }
    }
}