C# 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

using System;  
using System.Collections.Generic;  
using System.Linq;  
using System.Text;  
using System.Text.RegularExpressions;  
  
namespace BIReportCenter.Utility  
{  
    public class StringHelper  
    {  
        #region String length formatter  
  
        /// 
  
        /// 对字符串进行裁剪  
        /// 
  
        public static string Trim(string stringTrim, int maxLength)  
        {  
            return Trim(stringTrim, maxLength, "...");  
        }  
  
        /// 
  
        /// 对字符串进行裁剪(区分单字节及双字节字符)  
        /// 
  
        /// 需要裁剪的字符串  
        /// 裁剪的长度，按双字节计数  
        /// 如果进行了裁剪需要附加的字符  
        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  
  
        /// 
  
        /// 检测是否有Sql危险字符  
        /// 
  
        /// 要判断字符串  
        /// 判断结果  
        public static bool IsSafeSqlString(string str)  
        {  
            return !Regex.IsMatch(str, @"[-|;|,|\/|\(|\)|\[|\]|\}|\{|%|@|\*|!|\']");  
        }  
  
        /// 
  
        /// 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  
        /// 
  
        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", "
");  
            Parameter = Parameter.Replace("\0", "·");  
            return Parameter;  
        }  
  
        /// 
  
        /// 清除xml中的不合法字符  
        /// 
  
        ///   
        /// 无效字符：  
        /// 0x00 - 0x08  
        /// 0x0b - 0x0c  
        /// 0x0e - 0x1f  
        ///   
        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("�", "");  
                //return Regex.Replace(result, @"[\?-\\ \ \-\\?-\?]", delegate(Match m) { int code = (int)m.Value.ToCharArray()[0]; return (code > 9 ? "&#" + code.ToString() : "�" + code.ToString()) + ";"; });  
            }  
        }  
  
  
        /// 
  
        /// 改正sql语句中的转义字符  
        /// 
  
        public static string mashSQL(string str)  
        {  
            return (str == null) ? "" : str.Replace("\'", "'");  
        }  
  
        /// 
  
        /// 替换sql语句中的有问题符号 
        /// 
  
        public static string ChkSQL(string str)  
        {  
            return (str == null) ? "" : str.Replace("'", "''");  
        }   
  
        /// 
  
        ///  判断是否有非法字符 
        /// 
  
        ///   
        /// 返回TRUE表示有非法字符，返回FALSE表示没有非法字符。  
        public static bool CheckBadStr(string strString)  
        {  
            bool outValue = false;  
            if (strString != null && strString.Length > 0)  
            {  
                string[] bidStrlist = new string[9];  
                bidStrlist[0] = "'";  
                bidStrlist[1] = ";";  
                bidStrlist[2] = ":";  
                bidStrlist[3] = "%";  
                bidStrlist[4] = "@";  
                bidStrlist[5] = "&";  
                bidStrlist[6] = "#";  
                bidStrlist[7] = "\"";  
                bidStrlist[8] = "net user";  
                bidStrlist[9] = "exec";  
                bidStrlist[10] = "net localgroup";  
                bidStrlist[11] = "select";  
                bidStrlist[12] = "asc";  
                bidStrlist[13] = "char";  
                bidStrlist[14] = "mid";  
                bidStrlist[15] = "insert";  
                bidStrlist[19] = "order";  
                bidStrlist[20] = "exec";  
                bidStrlist[21] = "delete";  
                bidStrlist[22] = "drop";  
                bidStrlist[23] = "truncate";  
                bidStrlist[24] = "xp_cmdshell";  
                bidStrlist[25] = "<";  
                bidStrlist[26] = ">";  
                string tempStr = strString.ToLower();  
                for (int i = 0; i < bidStrlist.Length; i++)  
                {  
                    if (tempStr.IndexOf(bidStrlist[i]) != -1)  
                    //if (tempStr == bidStrlist[i])  
                    {  
                        outValue = true;  
                        break;  
                    }  
                }  
            }  
            return outValue;  
        }  
 
        #endregion  
 
        #region Tools  
        /// 
  
        /// 去掉最后一个逗号  
        /// 
  
        /// 要做处理的字符串  
        /// 去掉最后一个逗号的字符串  
        public static string DelLastComma(string String)  
        {  
            if (String.IndexOf(",") == -1)  
            {  
                return String;  
            }  
            return String.Substring(0, String.LastIndexOf(","));  
        }  
  
        /// 
  
        /// 删除最后一个字符  
        /// 
  
        ///   
        ///   
        public static string ClearLastChar(string str)  
        {  
            return (str == "") ? "" : str.Substring(0, str.Length - 1);  
        }  
        /// 
  
        /// html编码  
        /// 
  
        ///   
        ///   
        public static string html_text(string chr)  
        {  
            if (chr == null)  
                return "";  
            chr = chr.Replace("'", "''");  
            chr = chr.Replace("<", "<");  
            chr = chr.Replace(">", ">");  
            return (chr);  
        }  
        /// 
  
        /// html解码  
        /// 
  
        ///   
        ///   
        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("
", "\n").Replace("<", "<").Replace(">", ">").Replace(" ", " ");  
            return OutputString;  
  
        }  
        #endregion  
    }  
}