今天看到Google PageRank ChecksumPHP代码才发现上次发布的库写的很烂，我根本没有去理解里面的意思，有很多函数是没有必要的，如<< >>位操作都已经是现成的，我怎么还照着vb代码改写，真是愚蠢。
为了弥补我的愚蠢，把php代码改编成的.net库,发布出来。
Google PageRank 链接库下载地址：http://code.knowsky.com/down/2847.html
演示地址：http://pr.csharphack.org/checkpr.aspx
使用实例：
//得到Pagerank值
Console.WriteLine(PRCrack.PageRank.CheckPR("http://www.google.com"));
//得到pagerank checksum
Console.WriteLine(PRCrack.PageRank.OutputCheckSum("http://www.google.com",1));
包含函数：
//输出指定网址的pagerank checksum
//参数m_Version指定１，表示得到新版本checksum，Google Toolbar版本>>=2.0.114
//参数m_Version指定０，表示得到老版本checksum，Google Toolbar版本<2.0.114
public static string OutputCheckSum(string m_Url,int m_Version)
//输出制定网址的pagerank
public static string CheckPR(string m_Url)
Checksum 算法源代码请看详细内容
1using System;
2
3namespace PRCrack
4{
5 /// <summary>
6 /// Google PageRank的Checksum算法。
7 /// 作者:4111y80y
8 /// 日期:2005年1月22日
9 /// email:sillyboy@china.com
10 /// </summary>
11 class CheckSum
12 {
13 public CheckSum()
14 {
15 //
16 // TODO: 在此处添加构造函数逻辑
17 //
18 }
19
20 uint GOOGLE_MAGIC=0xE6359A60;
21
22 private uint zeroFill(uint a, int b)
23 {
24 checked
25 {
26 uint z = 0x80000000;
27 if (Convert.ToBoolean(z & a))
28 {
29 a = (a>>1);
30 a &= (~z);
31 a |= 0x40000000;
32 a = (a>>(b-1));
33 }
34 else
35 {
36 a = (a>>b);
37 }
38 }
39 return a;
40 }
41
42 private uint[] mix(uint a,uint b,uint c)
43 {
44 a -= b; a -= c; a ^= (uint)(zeroFill(c,13));
45 b -= c; b -= a; b ^= (uint)(a<<8);
46 c -= a; c -= b; c ^= (uint)(zeroFill(b,13));
47 a -= b; a -= c; a ^= (uint)(zeroFill(c,12));
48 b -= c; b -= a; b ^= (uint)(a<<16);
49 c -= a; c -= b; c ^= (uint)(zeroFill(b,5));
50 a -= b; a -= c; a ^= (uint)(zeroFill(c,3));
51 b -= c; b -= a; b ^= (uint)(a<<10);
52 c -= a; c -= b; c ^= (uint)(zeroFill(b,15));
53
54 return new uint[3]{a,b,c};
55 }
56
57 private uint GoogleCH(uint[] url, uint length, uint init)
58 {
59 if(length==0)
60 {
61 length = (uint)url.Length;
62 }
63 uint a ,b;
64 a=b= 0x9E3779B9;
65 uint c = init;
66 int k = 0;
67 uint len = length;
68 uint[] m_mix=new uint[3];
69 while(len >= 12)
70 {
71 a += (uint)(url[k+0] +(url[k+1]<<8) +(url[k+2]<<16) +(url[k+3]<<24));
72
73 b += (uint)(url[k+4] +(url[k+5]<<8) +(url[k+6]<<16) +(url[k+7]<<24));
74 c += (uint)(url[k+8] +(url[k+9]<<8) +(url[k+10]<<16)+(url[k+11]<<24));
75 m_mix = mix(a,b,c);
76 a = m_mix[0]; b = m_mix[1]; c = m_mix[2];
77
78 k += 12;
79 len -= 12;
80 }
81
82 c += length;
83
84 switch(len) /* all the case statements fall through */
85 {
86 case 11:
87 {
88 c+=(uint)(url[k+10]<<24);
89 c+=(uint)(url[k+9]<<16);
90 c+=(uint)(url[k+8]<<8);
91 b+=(uint)(url[k+7]<<24);
92 b+=(uint)(url[k+6]<<16);
93 b+=(uint)(url[k+5]<<8);
94 b+=(uint)(url[k+4]);
95 a+=(uint)(url[k+3]<<24);
96 a+=(uint)(url[k+2]<<16);
97 a+=(uint)(url[k+1]<<8);
98 a+=(uint)(url[k+0]);
99 break;
100 }
101 case 10:
102 {
103 c+=(uint)(url[k+9]<<16);
104 c+=(uint)(url[k+8]<<8);
105 b+=(uint)(url[k+7]<<24);
106 b+=(uint)(url[k+6]<<16);
107 b+=(uint)(url[k+5]<<8);
108 b+=(uint)(url[k+4]);
109 a+=(uint)(url[k+3]<<24);
110 a+=(uint)(url[k+2]<<16);
111 a+=(uint)(url[k+1]<<8);
112 a+=(uint)(url[k+0]);
113 break;
114 }
115 case 9 :
116 {
117 c+=(uint)(url[k+8]<<8);
118 b+=(uint)(url[k+7]<<24);
119 b+=(uint)(url[k+6]<<16);
120 b+=(uint)(url[k+5]<<8);
121 b+=(uint)(url[k+4]);
122 a+=(uint)(url[k+3]<<24);
123 a+=(uint)(url[k+2]<<16);
124 a+=(uint)(url[k+1]<<8);
125 a+=(uint)(url[k+0]);
126 break;
127 }
128 /* the first byte of c is reserved for the length */
129 case 8 :
130 {
131 b+=(uint)(url[k+7]<<24);
132 b+=(uint)(url[k+6]<<16);
133 b+=(uint)(url[k+5]<<8);
134 b+=(uint)(url[k+4]);
135 a+=(uint)(url[k+3]<<24);
136 a+=(uint)(url[k+2]<<16);
137 a+=(uint)(url[k+1]<<8);
138 a+=(uint)(url[k+0]);
139 break;
140 }
141 case 7 :
142 {
143 b+=(uint)(url[k+6]<<16);
144 b+=(uint)(url[k+5]<<8);
145 b+=(uint)(url[k+4]);
146 a+=(uint)(url[k+3]<<24);
147 a+=(uint)(url[k+2]<<16);
148 a+=(uint)(url[k+1]<<8);
149 a+=(uint)(url[k+0]);
150 break;
151 }
152 case 6 :
153 {
154 b+=(uint)(url[k+4]);
155 a+=(uint)(url[k+3]<<24);
156 a+=(uint)(url[k+2]<<16);
157 a+=(uint)(url[k+1]<<8);
158 a+=(uint)(url[k+0]);
159 break;
160 }
161 case 5 :
162 {
163 b+=(uint)(url[k+4]);
164 a+=(uint)(url[k+3]<<24);
165 a+=(uint)(url[k+2]<<16);
166 a+=(uint)(url[k+1]<<8);
167 a+=(uint)(url[k+0]);
168 break;
169 }
170 case 4 :
171 {
172 a+=(uint)(url[k+3]<<24);
173 a+=(uint)(url[k+2]<<16);
174 a+=(uint)(url[k+1]<<8);
175 a+=(uint)(url[k+0]);
176 break;
177 }
178 case 3 :
179 {
180 a+=(uint)(url[k+2]<<16);
181 a+=(uint)(url[k+1]<<8);
182 a+=(uint)(url[k+0]);
183 break;
184 }
185 case 2 :
186 {
187 a+=(uint)(url[k+1]<<8);
188 a+=(uint)(url[k+0]);
189 break;
190 }
191 case 1 :
192 {
193 a+=(uint)(url[k+0]);
194 break;
195 }
196 /* case 0: nothing left to add */
197 }
198 m_mix = mix(a,b,c);
199 /*-------------------------------------------- report the result */
200 return m_mix[2];
201 }
202
203 private uint GoogleCH(string url, uint length)
204 {
205 uint[] m_urluint=new uint[url.Length];
206 for(int i=0;i<url.Length;i++)
207 {
208 m_urluint[i]=url[i];
209 }
210 return GoogleCH(m_urluint,length,GOOGLE_MAGIC);
211 }
212
213 private uint GoogleCH(string sURL)
214 {
215 return GoogleCH(sURL,0);
216 }
217
218 private uint GoogleCH(uint[] url, uint length)
219 {
220 return GoogleCH(url, length, GOOGLE_MAGIC);
221 }
222
223 private uint[] c32to8bit(uint[] arr32)
224 {
225 uint[] arr8=new uint[arr32.GetLength(0)*4+3];
226
227 for(int i=0;i<arr32.GetLength(0);i++)
228 {
229 for (int bitOrder=i*4;bitOrder<=i*4+3;bitOrder++)
230 {
231 arr8[bitOrder]=arr32[i]&255;
232 arr32[i]=zeroFill(arr32[i], 8);
233 }
234 }
235 return arr8;
236 }
237
238 //新算法,ToolBar 版本>>=2.0.114
239 public string CalculateChecksum(string sURL)
240 {
241 uint ch=GoogleCH("info:" + sURL);
242
243 ch = (((ch/7) << 2) | (((uint)(ch%13))&7));
244
245 uint[] prbuf = new uint[20];
246 prbuf[0] = ch;
247 for(int i = 1; i < 20; i++) {
248 prbuf[i] = prbuf[i-1]-9;
249 }
250 ch = GoogleCH(c32to8bit(prbuf), 80);
251
252 return string.Format("6{0}",ch);
253 }
254
255 //老算法,ToolBar 版本<2.0.114
256 public string CalculateChecksumOld(string sURL)
257 {
258 uint ch=GoogleCH("info:" + sURL);
259
260 string CalculateChecksum = "6" + Convert.ToString((ch));
261 return CalculateChecksum;
262 }
263 }
264}
