.Net防sql注入的几种方法

public class SqlInjectHelper:System.Web.UI.Page
 {
  private static string StrKeyWord = "select|insert|delete|from|count(|drop table|update|truncate|asc(|mid(|char(|xp_cmdshell|exec|master|net local group administrators|net user|or|and";
  private static string StrSymbol = ";|(|)|[|]|{|}|%|@|*|'|!";

  private HttpRequest request;
  public SqlInjectHelper(System.Web.HttpRequest _request)
  {
   this.request = _request;
  }
  public bool CheckSqlInject()
  {
   return CheckRequestQuery() || CheckRequestForm();
  }

  ///<summary> 
  ///检查URL中是否包含Sql注入 
  /// <param name="_request">当前HttpRequest对象</param> 
  /// <returns>如果包含sql注入关键字，返回：true;否则返回：false</returns> 
  ///</summary> 
  public bool CheckRequestQuery()
  {
   if (request.QueryString.Count > 0)
   {
    foreach (string sqlParam in this.request.QueryString)
    {
     if (sqlParam == "__VIEWSTATE") 
      continue;
     if (sqlParam == "__EVENTVALIDATION") 
      continue;
     if (CheckKeyWord(request.QueryString[sqlParam].ToLower()))
     {
      return true;
     }
    }
   }
   return false;
  }
  ///<summary> 
  ///检查提交的表单中是否包含Sql注入关键字
  /// <param name="_request">当前HttpRequest对象</param> 
  /// <returns>如果包含sql注入关键字，返回：true;否则返回：false</returns> 
  ///</summary> 
  public bool CheckRequestForm()
  {
   if (request.Form.Count > 0)
   {
    foreach (string sqlParam in this.request.Form)
    {
     if (sqlParam == "__VIEWSTATE") 
      continue;
     if (sqlParam == "__EVENTVALIDATION") 
      continue;
     if (CheckKeyWord(request.Form[sqlParam]))
     {
      return true;
     }
    }
   }
   return false;
  }
  ///<summary> 
  ///检查字符串中是否包含Sql注入关键字 
  /// <param name="_key">被检查的字符串</param> 
  /// <returns>如果包含sql注入关键字，返回：true;否则返回：false</returns> 
  ///</summary> 
  private static bool CheckKeyWord(string _key)
  {
   string[] pattenKeyWord = StrKeyWord.Split('|');
   string[] pattenSymbol = StrSymbol.Split('|');
   foreach (string sqlParam in pattenKeyWord)
   {
    if (_key.Contains(sqlParam + " ") || _key.Contains(" " + sqlParam))
    {
     return true;
    }
   }
   foreach (string sqlParam in pattenSymbol)
   {
    if (_key.Contains(sqlParam))
    {
     return true;
    }
   }
   return false;
  }

 }

protected void Application_BeginRequest(object sender, EventArgs e)
  {
   SqlInjectHelper myCheck = new SqlInjectHelper(Request);
   bool result = myCheck.CheckSqlInject();
   if (result)
   {
    Response.ContentType = "text/plain";
    Response.Write("您提交的数据有恶意字符！");
    Response.End();
   }
  }

public class Handler1 : IHttpHandler
 {
  public void ProcessRequest(HttpContext context)
  {
   SqlInjectHelper myCheck = new SqlInjectHelper(context.Request);
   bool result = myCheck.CheckSqlInject();
   context.Response.ContentType = "text/plain";
   context.Response.Write(result?"您提交的数据有恶意字符！":"");
   context.Response.StatusCode = result ? 500 : 200;
  }
  public bool IsReusable
  {
   get
   {
    return false;
   }
  }
 }

public class SafeHelper
 {
  private const string StrRegex = @"<[^>]+?style=[\w]+?:expression\(|\b(alert|confirm|prompt)\b|^\+/v(8|9)|<[^>]*?=[^>]*?&#[^>]*?>|\b(and|or)\b.{1,6}?(=|>|<|\bin\b|\blike\b)|/\*.+?\*/|<\s*script\b|<\s*img\b|\bEXEC\b|UNION.+?SELECT|UPDATE.+?SET|INSERT\s+INTO.+?VALUES|(SELECT|DELETE).+?FROM|(CREATE|ALTER|DROP|TRUNCATE)\s+(TABLE|DATABASE)";
  public static bool PostData()
  {
   bool result = false;
   for (int i = 0; i < HttpContext.Current.Request.Form.Count; i++)
   {
    result = CheckData(HttpContext.Current.Request.Form[i].ToString());
    if (result)
    {
     break;
    }
   }
   return result;
  }

  public static bool GetData()
  {
   bool result = false;
   for (int i = 0; i < HttpContext.Current.Request.QueryString.Count; i++)
   {
    result = CheckData(HttpContext.Current.Request.QueryString[i].ToString());
    if (result)
    {
     break;
    }
   }
   return result;
  }
  public static bool CookieData()
  {
   bool result = false;
   for (int i = 0; i < HttpContext.Current.Request.Cookies.Count; i++)
   {
    result = CheckData(HttpContext.Current.Request.Cookies[i].Value.ToLower());
    if (result)
    {
     break;
    }
   }
   return result;

  }
  public static bool referer()
  {
   bool result = false;
   return result = CheckData(HttpContext.Current.Request.UrlReferrer.ToString());
  }
  public static bool CheckData(string inputData)
  {
   if (Regex.IsMatch(inputData, StrRegex))
   {
    return true;
   }
   else
   {
    return false;
   }
  }
 }