C#字符串工具類，實現的功能包括：判斷某值是否在枚舉內(位枚舉)、將全角數字轉換為數字、判斷是否為IP、獲得當前頁面客戶端的IP、改正sql語句中的轉義字符、檢測是否是正確的Url、檢測是否符合email格式、SQL字符串過濾、按字節數截取字符串(不帶省略號)、按字節數截取字符串(後面加省略號...)等。
view sourceprint?001using System;
002using System.Collections.Generic;
003using System.Linq;
004using System.Text;
005using System.Text.RegularExpressions;
006using System.Web;
007namespace CLB.Utility.CharTools
008{
009 public static class StringHelper
010 {
011 /// <summary>
012 /// 按字節數截取字符串(後面加省略號...) 013 /// </summary>
014 ///<param name="origStr"> 原始字符串</param>
015 ///<param name="endIndex"> 提取前endIdex個字節</param>
016 /// <returns></returns>
017 public static string GetSubString(string origStr, int endIndex)
018 {
019 if (origStr == null || origStr.Length == 0 || endIndex < 0)
020 return "";
021 int bytesCount = System.Text.Encoding.GetEncoding("gb2312").GetByteCount(origStr);
022 if (bytesCount > endIndex)
023 {
024 int readyLength = 0;
025 int byteLength;
026 for (int i = 0; i < origStr.Length; i++)
027 {
028 byteLength = System.Text.Encoding.GetEncoding("gb2312").GetByteCount(new char[] { origStr[i] });
029 readyLength += byteLength;
030 if (readyLength == endIndex)
031 {
032 origStr = origStr.Substring(0, i + 1) + "...";
033 break;
034 }
035 else if (readyLength > endIndex)
036 {
037 origStr = origStr.Substring(0, i) + "...";
038 break;
039 }
040 }
041 }
042 return origStr;
043 }
044 /// <summary>
045 /// 按字節數截取字符串(不帶省略號) 046 /// </summary>
047 /// <param name="origStr"> 原始字符串</param>
048 /// <param name="endIndex"> 提取前endIdex個字節</param>
049 /// <returns></returns>
050 public static string GetSub1String(string origStr, int endIndex)
051 {
052 if (origStr == null || origStr.Length == 0 || endIndex < 0)
053 return "";
054 int bytesCount = System.Text.Encoding.GetEncoding("gb2312").GetByteCount(origStr);
055 if (bytesCount > endIndex)
056 {
057 int readyLength = 0;
058 int byteLength;
059 for (int i = 0; i < origStr.Length; i++)
060 {
061 byteLength = System.Text.Encoding.GetEncoding("gb2312").GetByteCount(new char[] { origStr[i] });
062 readyLength += byteLength;
063 if (readyLength == endIndex)
064 {
065 origStr = origStr.Substring(0, i + 1);
066 break;
067 }
068 else if (readyLength > endIndex)
069 {
070 origStr = origStr.Substring(0, i);
071 break;
072 }
073 }
074 }
075 return origStr;
076 }
077 /// <summary>
078 /// SQL字符串過濾 079 /// </summary>
080 /// <param name="Str"></param>
081 /// <returns></returns>
082 public static bool ProcessSqlStr(string Str)
083 {
084 bool ReturnValue = true;
085 try
086 {
087 if (Str.Trim() != "")
088 {
089 string SqlStr ="exec|insert+|select+|delete|update|count|chr|mid|master+
|truncate|char|declare|drop+|drop
+table|creat+|create|*|iframe|script|";
090 SqlStr +="exec+|insert|delete+|update+|count(|count+|chr+|+mid
(|+mid+|+master+|truncate+
|char+|+char(|declare
+|drop+table|creat+table";
091 string[] anySqlStr = SqlStr.Split('|');
092 foreach (string ss in anySqlStr)
093 {
094 if (Str.ToLower().IndexOf(ss) >= 0)
095 {
096 ReturnValue = false;
097 break;
098 }
099 }
100 }
101 }
102 catch
103 {
104 ReturnValue = false;
105 }
106 return ReturnValue;
107 }
108 /// <summary>
109 /// 檢測是否符合email格式 110 /// </summary>
111 /// <param name="strEmail"> 要判斷的email字符串</param>
112 ///<returns
113 public static bool IsValidEmail(string strEmail)
114 {
115 return Regex.IsMatch(strEmail, @"^([w-.]+)@(([[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.)|(([w-]+.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(]?)$");
116 }
117 /// <summary>
118 /// 檢測是否是正確的Url 119 /// </summary>
120 /// <param name="strUrl"> 要驗證的Url</param>
121 /// <returns>
122 public static bool IsURL(string strUrl)
123 {
124 return Regex.IsMatch(strUrl, @"^(http|https)://([a-zA-Z0-9.-]+(:[a-zA-Z0-9.&%$-]+)*@)*((25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]).(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0).(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0).(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])|localhost|([a-zA-Z0-9-]+.)*[a-zA-Z0-9-]+.(com|edu|gov|int|mil|net|org|biz|arpa|info|name|pro|aero|coop|museum|[a-zA-Z]{1,10}))(:[0-9]+)*(/($|[a-zA-Z0-9.,?'+&%$#=~_-]+))*$");
125 }
126 /// <summary>
127 /// 檢測是否有Sql危險字符 128 /// </summary>
129 /// <param name="str"> 要判斷字符串</param>
130 ///<returns>
131 public static bool IsSafeSqlString(string str)
132 {
133 return !Regex.IsMatch(str, @"[-|;|,|/|(|)|[|]|}|{|%|@|*|!|']");
134 }
135 /// <summary>
136 /// 改正sql語句中的轉義字符 137 /// </summary>
138 public static string mashSQL(string str)
139 {
140 string str2;
141 if (str == null)
142 {
143 str2 = "";
144 }
145 else
146 {
147 str = str.Replace("'", "'");
148 str2 = str;
149 }
150 return str2;
151 }
152 /// <summary>
153 /// 獲得當前頁面客戶端的IP 154 /// </summary>
155 /// <returns>
156 public static string GetIP()
157 {
158 string result = String.Empty;
159 result = HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
160 if (null == result || result == String.Empty)
161 {
162 result = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
163 }
164 if (null == result || result == String.Empty)
165 {
166 result = HttpContext.Current.Request.UserHostAddress;
167 }
168 if (null == result || result == String.Empty || !IsIP(result))
169 {
170 return "0.0.0.0";
171 }
172 return result;
173 }
174 /// <summary>
175 /// 是否為ip 176 /// </summary>
177 /// <param name="ip"></param>
178 /// <returns></returns>
179 public static bool IsIP(string ip)
180 {
181 return Regex.IsMatch(ip, @"^((2[0-4]d|25[0-5]|[01]?dd?).){3}(2[0-4]d|25[0-5]|[01]?dd?)$");
182 }
183 /// <summary>
184 /// 將全角數字轉換為數字 185 /// </summary>
186 /// <param name="SBCCase"></param>
187 /// <returns></returns>
188 public static string SBCCaseToNumberic(string SBCCase)
189 {
190 char[] c = SBCCase.ToCharArray();
191 for (int i = 0; i < c.Length; i++)
192 {
193 byte[] b = System.Text.Encoding.Unicode.GetBytes(c, i, 1);
194 if (b.Length == 2)
195 {
196 if (b[1] == 255)
197 {
198 b[0] = (byte)(b[0] + 32);
199 b[1] = 0;
200 c[i] = System.Text.Encoding.Unicode.GetChars(b)[0];
201 }
202 }
203 }
204 return new string(c);
205 }
206 /// <summary>
207 /// 判斷某值是否在枚舉內(位枚舉) 208 /// </summary>
209 ///<param name="checkingValue"> 被檢測的枚舉值</param>
210 ///<param name="expectedValue"> 期望的枚舉值</param>
211 /// <returns>
212 public static bool CheckFlagsEnumEquals(Enum checkingValue, Enum expectedValue)
213 {
214 int intCheckingValue = Convert.ToInt32(checkingValue);
215 int intExpectedValue = Convert.ToInt32(expectedValue);
216 return (intCheckingValue & intExpectedValue) == intExpectedValue;
217 }
218 }
219}
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