C# 防止SQL注入

using System;
using System.Text.RegularExpressions;
using System.Web;


/**//// <summary>
/// SqlKey 的摘要说明。
/// </summary>
public class SqlKey
{
private HttpRequest request;
private const string StrKeyWord = @"select|insert|delete|from|count(|drop table|update|truncate|asc(|mid(|char(|xp_cmdshell|exec master|netlocalgroup administrators|:|net user|""|or|and";
private const string StrRegex = @"-|;|,|/|(|)|[|]|}|{|%|@|*|!|‘";
public SqlKey(System.Web.HttpRequest _request)
{
//
// TODO: 在此处添加构造函数逻辑
//
this.request = _request;
}

/**//// <summary>
/// 只读属性 SQL关键字
/// </summary>
public static string KeyWord
{
get
{
return StrKeyWord;
}
}
/**//// <summary>
/// 只读属性过滤特殊字符
/// </summary>
public static string RegexString
{
get
{
return StrRegex;
}
}
/**//// <summary>
/// 检查URL参数中是否带有SQL注入可能关键字。
/// </summary>
/// <param name="_request">当前HttpRequest对象</param>
/// <returns>存在SQL注入关键字true存在，false不存在</returns>
public bool CheckRequestQuery()
{
if (request.QueryString.Count != 0)
{
//若URL中参数存在，逐个比较参数。
foreach (string i in this.request.QueryString)
{
// 检查参数值是否合法。
if (i == "__VIEWSTATE") continue;
if (i == "__EVENTVALIDATION") continue;
if (CheckKeyWord(request.QueryString[i].ToString()))
{
return true;
}
}
}
return false;
}

/**//// <summary>
/// 检查提交表单中是否存在SQL注入可能关键字
/// </summary>
/// <param name="_request">当前HttpRequest对象</param>
/// <returns>存在SQL注入关键字true存在，false不存在</returns>
public bool CheckRequestForm()
{
if (request.Form.Count > 0)
{

//获取提交的表单项不为0 逐个比较参数
foreach (string i in this.request.Form)
{
if (i == "__VIEWSTATE") continue;
if (i == "__EVENTVALIDATION") continue;
//检查参数值是否合法
if (CheckKeyWord(request.Form[i]))
{
//存在SQL关键字
return true;

}
}
}
return false;
}

/**//// <summary>
/// 静态方法，检查_sword是否包涵SQL关键字
/// </summary>
/// <param name="_sWord">被检查的字符串</param>
/// <returns>存在SQL关键字返回true，不存在返回false</returns>
public static bool CheckKeyWord(string _sWord)
{
string word=_sWord;
string[] patten1 = StrKeyWord.Split(‘|‘);
string[] patten2 = StrRegex.Split(‘|‘);
foreach (string i in patten1)
{
if (word.Contains(" " + i) || word.Contains(i + " "))
{
return true;
}
}
foreach (string i in patten2)
{
if (word.Contains(i))
{
return true;
}
}
return false;
}

/**//// <summary>
/// 反SQL注入:返回1无注入信息，否则返回错误处理
/// </summary>
/// <returns>返回1无注入信息，否则返回错误处理</returns>
public string CheckMessage()
{
string msg = "1";
if (CheckRequestQuery()) //CheckRequestQuery() || CheckRequestForm()
{
//msg = "<span style=‘font-size:24px;‘>非法操作！<br>";
//msg += "操作IP：" + request.ServerVariables["REMOTE_ADDR"] + "<br>";
//msg += "操作时间：" + DateTime.Now + "<br>";
//msg += "页面：" + request.ServerVariables["URL"].ToLower() + "<br>";
//msg += "<a href="http://www.mamicode.com/#" onclick="history.back()">返回上一页</a></span>";
}
return msg.ToString();
}
}

void Application_BeginRequest(Object sender, EventArgs e)
{
SqlKey myCheck = new SqlKey(this.Request);
bool a = myCheck.CheckRequestForm();
bool b = myCheck.CheckRequestQuery();
if (myCheck.CheckRequestForm() || myCheck.CheckRequestQuery())
{
Response.Write("有");
}
else
{
Response.Write("无");
}

}