我的C#入门之路_Day4

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 using System.IO;
 7 
 8 
 9 namespace ConsoleApplication1
10 {
11     class Program
12     {
13         static Int64 a(int length, byte[] data)
14         {
15             Int64 CRCtemp = 65535;
16             int j = 0;
17             int chr = 0;
18             int chr1 = 0;
19             for (int y = 0; y < length; y++)
20             {
21                 chr = (int)CRCtemp & 255;
22                 chr = chr ^ data[j];
23                 CRCtemp = CRCtemp & 0xff00;
24                 CRCtemp = CRCtemp + chr;
25                 for (int i = 0; i < 8; i++)
26                 {
27                     if ((CRCtemp & 0x01) == 1)
28                     {
29                         CRCtemp = CRCtemp >> 1;
30                         CRCtemp = CRCtemp ^ 0xA001;
31 
32                     }
33                     else
34                     {
35                         CRCtemp = CRCtemp >> 1;
36                     }
37                 }
38                 j += 1;
39             }
40             chr = (int)CRCtemp & 0xff;
41             chr1 = (int)CRCtemp & 0xff00;
42             CRCtemp = chr << 8 | chr1 >> 8;
43             return CRCtemp;
44         }
45         static void Main(string[] args)
46         {
47             string str;
48             Console.WriteLine("input your file please:");
49             str = Console.ReadLine();
50             FileStream fs = new FileStream(str, FileMode.Open);
51             byte[] bt = new byte[1000];
52             int i = 0;
53             BinaryReader br = new BinaryReader(fs);
54             while(br.PeekChar() >= 0)
55             {
56                 bt[i] = br.ReadByte();
57                 i++;
58             }
59             Int64 result;
60             result = a(i, bt);
61             Console.WriteLine("the result is 0x" + result);
62             
63             
64 
65         }
66     }
67 }