C#(ASP.NET)正则表达式 过滤危险字符函数代码 防SQL注入 很全面的SQL关键字过滤

来源:互联网 发布:pc软件是什么意思啊 编辑:程序博客网 时间:2024/05/16 11:08
sing System;  using System.Collections.Generic;  using System.Linq;  using System.Text;  using System.Collections;using System.Text.RegularExpressions;    namespace BIReportCenter.Utility  {      public class StringHelper      {          #region String length formatter            /// <summary>          /// 对字符串进行裁剪          /// </summary>          public static string Trim(string stringTrim, int maxLength)          {              return Trim(stringTrim, maxLength, "...");          }            /// <summary>          /// 对字符串进行裁剪(区分单字节及双字节字符)          /// </summary>          /// <param name="rawString">需要裁剪的字符串</param>          /// <param name="maxLength">裁剪的长度,按双字节计数</param>          /// <param name="appendString">如果进行了裁剪需要附加的字符</param>          public static string Trim(string rawString, int maxLength, string appendString)          {              if (string.IsNullOrEmpty(rawString) || rawString.Length <= maxLength)              {                  return rawString;              }              else              {                  int rawStringLength = Encoding.UTF8.GetBytes(rawString).Length;                  if (rawStringLength <= maxLength * 2)                      return rawString;              }                int appendStringLength = Encoding.UTF8.GetBytes(appendString).Length;              StringBuilder checkedStringBuilder = new StringBuilder();              int appendedLenth = 0;              for (int i = 0; i < rawString.Length; i++)              {                  char _char = rawString[i];                  checkedStringBuilder.Append(_char);                    appendedLenth += Encoding.Default.GetBytes(new char[] { _char }).Length;                    if (appendedLenth >= maxLength * 2 - appendStringLength)                      break;              }                return checkedStringBuilder.ToString() + appendString;          }            #endregion           #region 特殊字符            /// <summary>          /// 检测是否有Sql危险字符          /// </summary>          /// <param name="str">要判断字符串</param>          /// <returns>判断结果</returns>          public static bool IsSafeSqlString(string str)          {              return !Regex.IsMatch(str, @"[-|;|,|\/|\(|\)|\[|\]|\}|\{|%|@|\*|!|\']");          }            /// <summary>          /// 删除SQL注入特殊字符          /// 解然 20070622加入对输入参数sql为Null的判断          /// </summary>          public static string StripSQLInjection(string sql)          {              if (!string.IsNullOrEmpty(sql))              {                  //过滤 ' --                  string pattern1 = @"(\%27)|(\')|(\-\-)";                    //防止执行 ' or                  string pattern2 = @"((\%27)|(\'))\s*((\%6F)|o|(\%4F))((\%72)|r|(\%52))";                    //防止执行sql server 内部存储过程或扩展存储过程                  string pattern3 = @"\s+exec(\s|\+)+(s|x)p\w+";                    sql = Regex.Replace(sql, pattern1, string.Empty, RegexOptions.IgnoreCase);                  sql = Regex.Replace(sql, pattern2, string.Empty, RegexOptions.IgnoreCase);                  sql = Regex.Replace(sql, pattern3, string.Empty, RegexOptions.IgnoreCase);              }              return sql;          }            public static string SQLSafe(string Parameter)          {              Parameter = Parameter.ToLower();              Parameter = Parameter.Replace("'", "");              Parameter = Parameter.Replace(">", ">");              Parameter = Parameter.Replace("<", "<");              Parameter = Parameter.Replace("\n", "<br>");              Parameter = Parameter.Replace("\0", "·");              return Parameter;          }            /// <summary>          /// 清除xml中的不合法字符          /// </summary>          /// <remarks>          /// 无效字符:          /// 0x00 - 0x08          /// 0x0b - 0x0c          /// 0x0e - 0x1f          /// </remarks>          public static string CleanInvalidCharsForXML(string input)          {              if (string.IsNullOrEmpty(input))                  return input;              else              {                  StringBuilder checkedStringBuilder = new StringBuilder();                  Char[] chars = input.ToCharArray();                  for (int i = 0; i < chars.Length; i++)                  {                      int charValue = Convert.ToInt32(chars[i]);                        if ((charValue >= 0x00 && charValue <= 0x08) || (charValue >= 0x0b && charValue <= 0x0c) || (charValue >= 0x0e && charValue <= 0x1f))                          continue;                      else                          checkedStringBuilder.Append(chars[i]);                  }                    return checkedStringBuilder.ToString();                    //string result = checkedStringBuilder.ToString();                  //result = result.Replace("&#x0;", "");                  //return Regex.Replace(result, @"[\?-\\ \ \-\\?-\?]", delegate(Match m) { int code = (int)m.Value.ToCharArray()[0]; return (code > 9 ? "&#" + code.ToString() : "&#0" + code.ToString()) + ";"; });              }          }              /// <summary>          /// 改正sql语句中的转义字符          /// </summary>          public static string mashSQL(string str)          {              return (str == null) ? "" : str.Replace("\'", "'");          }            /// <summary>          /// 替换sql语句中的有问题符号         /// </summary>          public static string ChkSQL(string str)          {              return (str == null) ? "" : str.Replace("'", "''");          }             /// <summary>          ///  判断是否有非法字符         /// </summary>          /// <param name="strString"></param>          /// <returns>返回TRUE表示有非法字符,返回FALSE表示没有非法字符。</returns>          public static bool CheckBadStr(string strString)          {              bool outValue = false;              if (strString != null && strString.Length > 0)              {                  ArrayList bidStrlist = new ArrayList();                       bidStrlist.Add("xp_cmdshell");                    bidStrlist.Add("truncate");                    bidStrlist.Add("net user");                    bidStrlist.Add("exec");                    bidStrlist.Add("net localgroup");                    bidStrlist.Add("select");                    bidStrlist.Add("asc");                    bidStrlist.Add("char");                    bidStrlist.Add("mid");                    bidStrlist.Add("insert");                    bidStrlist.Add("order");                    bidStrlist.Add("exec");                    bidStrlist.Add("delete");                    bidStrlist.Add("drop");                    bidStrlist.Add("truncate");                    bidStrlist.Add("1=1");                    bidStrlist.Add("1=2");                  string tempStr = strString.ToLower();                  for (int i = 0; i < bidStrlist.Length; i++)                  {                      if (tempStr.IndexOf(bidStrlist[i].ToString()) > -1)                                            {                          outValue = true;                          break;                      }                  }              }              return outValue;          }           #endregion           #region Tools          /// <summary>          /// 去掉最后一个逗号          /// </summary>          /// <param name="String">要做处理的字符串</param>          /// <returns>去掉最后一个逗号的字符串</returns>          public static string DelLastComma(string String)          {              if (String.IndexOf(",") == -1)              {                  return String;              }              return String.Substring(0, String.LastIndexOf(","));          }            /// <summary>          /// 删除最后一个字符          /// </summary>          /// <param name="str"></param>          /// <returns></returns>          public static string ClearLastChar(string str)          {              return (str == "") ? "" : str.Substring(0, str.Length - 1);          }          /// <summary>          /// html编码          /// </summary>          /// <param name="chr"></param>          /// <returns></returns>          public static string html_text(string chr)          {              if (chr == null)                  return "";              chr = chr.Replace("'", "''");              chr = chr.Replace("<", "<");              chr = chr.Replace(">", ">");              return (chr);          }          /// <summary>          /// html解码          /// </summary>          /// <param name="chr"></param>          /// <returns></returns>          public static string text_html(string chr)          {              if (chr == null)                  return "";              chr = chr.Replace("<", "<");              chr = chr.Replace(">", ">");              return (chr);          }          public static bool JustifyStr(string strValue)          {              bool flag = false;              char[] str = "^<>'=&*, ".ToCharArray(0, 8);              for (int i = 0; i < 8; i++)              {                  if (strValue.IndexOf(str[i]) != -1)                  {                      flag = true;                      break;                  }              }              return flag;          }          public static string CheckOutputString(string key)          {              string OutputString = string.Empty;              OutputString = key.Replace("<br>", "\n").Replace("<", "<").Replace(">", ">").Replace(" ", " ");              return OutputString;            }          #endregion      }  }