Asp.net数据库操作类_[Asp.Net教程]                                             using System;  
  using System.Data;  
  using System.Configuration;  
  using System.Web;  
  using System.Web.Security;  
  using System.Web.UI;  
  using System.Web.UI.WebControls;  
  using System.Web.UI.WebControls.WebParts;  
  using System.Web.UI.HtmlControls;  
  using System.Data.SqlClient;  
  namespace Mysqlserver  
  {  
   /// 
  
   /// SqlServerDataBase 的摘要说明  
   ///      public class SqlServerDataBase  
   {  
   private string strError = null;  
   private int intCount = 0;  
   public SqlServerDataBase()  
   {  
   //  
   // TODO: 在此处添加构造函数逻辑  
   //  
   }  
   /// 
  
   /// 公开方法DBConn,返回数据库连接  
   ///      /// 
     public SqlConnection DBconn()  
   {  
   string strConn = "Server=(local);Database=GlobalMeetings;Uid=sa;pwd=";  
   try  
   {  
   return new SqlConnection(strConn);  
   }  
   catch (Exception)  
   {  
   return null;  
   }  
   }  
   /// 
  
   /// 公开属性ErrorMessage,返回错误信息  
   ///      public string ErrorMessage  
   {  
   get  
   {  
   return strError;  
   }  
   }      
   /// 
  
   /// 根据查询语句从数据库检索数据  
   ///      /// 
查询语句  
   /// 
数据库连接  
   /// 
有数据则返回DataSet对象,否则返回null     public DataSet Select(string SelectString, SqlConnection sqlConn)  
   {  
   strError = "";  
   SqlConnection conn;  
   if (sqlConn == null)  
   {  
   conn = DBconn();  
   }  
   else  
   {  
   conn = sqlConn;  
   }  
   try  
   {  
   //若数据库连接的当前状态是关闭的,则打开连接  
   if (conn.State == ConnectionState.Closed)  
   {  
   conn.Open();  
   }  
   SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter();  
   SqlCommand selectCommand = new SqlCommand(SelectString, conn);  
   selectCommand.CommandType = CommandType.Text;  
   mySqlDataAdapter.SelectCommand = selectCommand;  
   DataSet myDS = new DataSet();  
   mySqlDataAdapter.Fill(myDS);  
   return myDS;  
   }  
   catch (Exception e)  
   {  
   strError = "数据检索失败:" + e.Message;  
   return null;  
   }  
   finally  
   {  
   if (conn.State != ConnectionState.Closed)  
   {  
   conn.Close();  
   }  
   }  
   }  
   /// 
  
   /// 更新数据库  
   ///      /// 
Update Sql语句  
   /// 
数据库连接  
   /// 
更新成功返回true     public bool Update(string UpdateString, SqlConnection SqlConn)  
   {  
   return udiDataBase(UpdateString, SqlConn);  
   }  
   /// 
  
   /// 从数据库中删除数据  
   ///      /// 
Delete Sql语句  
   /// 
数据库连接  
   /// 
删除成功返回true     public bool Delete(string DeleteString, SqlConnection SqlConn)  
   {  
   return udiDataBase(DeleteString, SqlConn);  
   }  
   /// 
  
   /// 把数据插入数据库  
   ///      /// 
Insert Sql语句  
   /// 
数据库连接  
   /// 
插入成功返回true     public bool Insert(string InsertString, SqlConnection SqlConn)  
   {  
   return udiDataBase(InsertString, SqlConn);  
   }  
   /// 
  
   /// 根据Sql语句更新数据库  
   ///      /// 
更新语句  
   /// 
数据库连接  
   /// 
更新成功则返回true     public bool udiDataBase(string UDIString, SqlConnection SqlConn)  
   {  
   strError = "";  
   SqlConnection conn;  
   if (SqlConn == null)  
   {  
   conn = DBconn();  
   }  
   else  
   {  
   conn = SqlConn;  
   }  
   try  
   {  
   if (conn.State == ConnectionState.Closed)  
   {  
   conn.Open();  
   }  
   SqlCommand cmd = new SqlCommand(UDIString, conn);  
   cmd.CommandType = CommandType.Text;  
   intCount = cmd.ExecuteNonQuery();  
   return !(intCount < 1);  
   }  
   catch (Exception e)  
   {  
   strError = "更新数据库失败:" + e.Message;  
   return false;  
   }  
   finally  
   {  
   if (conn.State != ConnectionState.Closed)  
   {  
   conn.Close();  
   }  
   }  
   }  
   }  
  }  
   -----------------------------  
  两种调用方法  
  1、 string strUserPsw = UserPsw.Text.Trim();  
   string UserPassword = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(strUserPsw, "MD5");//md5加密  
   SqlServerDataBase obj = new SqlServerDataBase();  
   obj.Insert("insert into asUserInfo (UserName,UserPassword,Question,Answer,CreateTime) values(’" + UserName.Text.Trim() + "’,’" + UserPassword + "’,’" + Question.Text.Trim() + "’,’" + Answer.Text.Trim() + "’,’" + DateTime.Now.ToString() + "’ )", null);  
  2、 private bool IsUsernameExist(string strUsername)  
   {  
   bool bRet = true;  
   SqlServerDataBase db = new SqlServerDataBase();  
   DataSet ds = db.Select("select * from asUserInfo where UserName = ’" + strUsername + "’", null);  
   if (ds == null || ds.Tables.Count == 0 || ds.Tables[0].Rows.Count == 0)  
   {  
   bRet = false;  
   }  
   else  
   {  
   bRet = true;  
   }      
   return bRet;  
   }      
  http://blog.csdn.net/zdyguilong/archive/2007/01/22/1490250.aspx