1 /*

  2  * Copyright (c) 2013 Thyiad

  3  * Author: Thyiad

  4  * Create date: 2013/08/08

  5  */

  6

  7 using System;

  8

  9 namespace Thyiad.Utility

 10 {

 11     /// <summary>

 12     /// Operates about string.

 13     /// </summary>

 14     public static class StringUtil

 15     {

 16         /// <summary>

 17         /// Compare with two string, return avg similar degree.

 18         /// </summary>

 19         /// <param name="str1"></param>

 20         /// <param name="str2"></param>

 21         /// <returns>A number of percent.</returns>

 22         public static int StrSim(string str1, string str2)

 23         {

 24             try

 25             {

 26                 if (str1 == null || str2 == null ||

 27                 (str1 == string.Empty && str2 != string.Empty) ||

 28                 (str1 != string.Empty && str2 == string.Empty))

 29                 {

 30                     return 0;

 31                 }

 32                 else if (str1.Equals(str2))

 33                 {

 34                     return 100;

 35                 }

 36

 37                 int similar1 = 0;

 38                 int similar2 = 0;

 39

 40                 similar1 = StrSimSub2(str1, str2);

 41                 similar2 = StrSimSub2(str2, str1);

 42

 43                 return ((similar1 + similar2) / 2);

 44             }

 45             catch (Exception)

 46             {

 47                 throw;

 48             }

 49         }

 50

 51         /// <summary>

 52         /// Compare with two string, return similar degree.

 53         /// </summary>

 54         /// <param name="str1"></param>

 55         /// <param name="str2"></param>

 56         /// <returns>A number of percent.</returns>

 57         private static int StrSimSub2(string str1, string str2)

 58         {

 59             try

 60             {

 61                 int len1, len2;

 62                 int pos1, pos2;

 63                 char char1, char2;

 64                 int val1, val_min, val_max;

 65

 66                 len1 = str1.Length;

 67                 len2 = str2.Length;

 68                 pos1 = 1;

 69                 val1 = 0;

 70

 71                 if (len1 < len2)

 72                 {

 73                     val_max = len2 + 1;

 74                 }

 75                 else

 76                 {

 77                     val_max = len1 + 1;

 78                 }

 79

 80                 while (pos1 <= len1)

 81                 {

 82                     char1 = str1[pos1 - 1];

 83                     pos2 = 1;

 84                     val_min = val_max;

 85                     while (pos2 <= len2)

 86                     {

 87                         char2 = str2[pos2 - 1];

 88                         if (char1 == char2)

 89                         {

 90                             if (Math.Abs(pos1 - pos2) < val_min)

 91                             {

 92                                 val_min = Math.Abs(pos1 - pos2);

 93                             }

 94                         }

 95                         pos2++;

 96                     }

 97                     pos1++;

 98                     val1 = val1 + val_min;

 99                 }

100

101                 return (100 - (val1 * 100 / (len1 * val_max)));

102             }

103             catch (Exception)

104             {

105                 throw;

106             }

107         }

108     }

109 }