using System;using System.Data;using System.Configuration;using System.Web;using System.Web.Security;using System.Collections;using System.Data.SqlClient;/// <summary>/// 数据库的通用访问代码/// 此类为抽象类，不允许实例化，在应用时直接调用即可/// </summary>public abstract class SqlHelper{ //获取数据库连接字符串，其属于静态变量且只读，项目中所有文档可以直接使用，但不能修改 public static readonly string ConnectionStringLocalTransaction = ConfigurationManager.ConnectionStrings["pubsConnectionString"].ConnectionString; // 哈希表用来存储缓存的参数信息，哈希表可以存储任意类型的参数。 private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable()); /// <summary> ///执行一个不需要返回值的SqlCommand命令，通过指定专用的连接字符串。 /// 使用参数数组形式提供参数列表 /// </summary> /// <remarks> /// 使用示例： /// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connectionString">一个有效的数据库连接字符串</param> /// <param name="commandType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param> /// <param name="commandText">存储过程的名字或者 T-SQL 语句</param> /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param> /// <returns>返回一个数值表示此SqlCommand命令执行后影响的行数</returns> public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) { SqlCommand cmd = new SqlCommand(); using (SqlConnection conn = new SqlConnection(connectionString)) { //通过PrePareCommand方法将参数逐个加入到SqlCommand的参数集合中 PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters); int val = cmd.ExecuteNonQuery(); //清空SqlCommand中的参数列表 cmd.Parameters.Clear(); return val; } } /// <summary> ///执行一条不返回结果的SqlCommand，通过一个已经存在的数据库连接 /// 使用参数数组提供参数 /// </summary> /// <remarks> /// 使用示例： /// int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="conn">一个现有的数据库连接</param> /// <param name="commandType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param> /// <param name="commandText">存储过程的名字或者 T-SQL 语句</param> /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param> /// <returns>返回一个数值表示此SqlCommand命令执行后影响的行数</returns> public static int ExecuteNonQuery(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) { SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters); int val = cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); return val; } /// <summary> /// 执行一条不返回结果的SqlCommand，通过一个已经存在的数据库事物处理 /// 使用参数数组提供参数 /// </summary> /// <remarks> /// 使用示例： /// int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="trans">一个存在的 sql 事物处理</param> /// <param name="commandType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param> /// <param name="commandText">存储过程的名字或者 T-SQL 语句</param> /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param> /// <returns>返回一个数值表示此SqlCommand命令执行后影响的行数</returns> public static int ExecuteNonQuery(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) { SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters); int val = cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); return val; } /// <summary> /// 执行一条返回结果集的SqlCommand命令，通过专用的连接字符串。 /// 使用参数数组提供参数 /// </summary> /// <remarks> /// 使用示例： /// SqlDataReader r = ExecuteReader(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connectionString">一个有效的数据库连接字符串</param> /// <param name="commandType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param> /// <param name="commandText">存储过程的名字或者 T-SQL 语句</param> /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param> /// <returns>返回一个包含结果的SqlDataReader</returns> public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) { SqlCommand cmd = new SqlCommand(); SqlConnection conn = new SqlConnection(connectionString); // 在这里使用try/catch处理是因为如果方法出现异常，则SqlDataReader就不存在， //CommandBehavior.CloseConnection的语句就不会执行，触发的异常由catch捕获。 //关闭数据库连接，并通过throw再次引发捕捉到的异常。 try { PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters); SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection); cmd.Parameters.Clear(); return rdr; } catch { conn.Close(); throw; } } /// <summary> /// 执行一条返回第一条记录第一列的SqlCommand命令，通过专用的连接字符串。 /// 使用参数数组提供参数 /// </summary> /// <remarks> /// 使用示例： /// Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connectionString">一个有效的数据库连接字符串</param> /// <param name="commandType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param> /// <param name="commandText">存储过程的名字或者 T-SQL 语句</param> /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param> /// <returns>返回一个object类型的数据，可以通过 Convert.To{Type}方法转换类型</returns> public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) { SqlCommand cmd = new SqlCommand(); using (SqlConnection connection = new SqlConnection(connectionString)) { PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters); object val = cmd.ExecuteScalar(); cmd.Parameters.Clear(); return val; } } /// <summary> /// 执行一条返回第一条记录第一列的SqlCommand命令，通过已经存在的数据库连接。 /// 使用参数数组提供参数 /// </summary> /// <remarks> /// 使用示例： /// Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="conn">一个已经存在的数据库连接</param> /// <param name="commandType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param> /// <param name="commandText">存储过程的名字或者 T-SQL 语句</param> /// <param name="commandParameters">以数组形式提供SqlCommand命令中用到的参数列表</param> /// <returns>返回一个object类型的数据，可以通过 Convert.To{Type}方法转换类型</returns> public static object ExecuteScalar(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters) { SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters); object val = cmd.ExecuteScalar(); cmd.Parameters.Clear(); return val; } /// <summary> /// 缓存参数数组 /// </summary> /// <param name="cacheKey">参数缓存的键值</param> /// <param name="cmdParms">被缓存的参数列表</param> public static void CacheParameters(string cacheKey, params SqlParameter[] commandParameters) { parmCache[cacheKey] = commandParameters; } /// <summary> /// 获取被缓存的参数 /// </summary> /// <param name="cacheKey">用于查找参数的KEY值</param> /// <returns>返回缓存的参数数组</returns> public static SqlParameter[] GetCachedParameters(string cacheKey) { SqlParameter[] cachedParms = (SqlParameter[])parmCache[cacheKey]; if (cachedParms == null) return null; //新建一个参数的克隆列表 SqlParameter[] clonedParms = new SqlParameter[cachedParms.Length]; //通过循环为克隆参数列表赋值 for (int i = 0, j = cachedParms.Length; i < j; i++) //使用clone方法复制参数列表中的参数 clonedParms[i] = (SqlParameter)((ICloneable)cachedParms[i]).Clone(); return clonedParms; } /// <summary> /// 为执行命令准备参数 /// </summary> /// <param name="cmd">SqlCommand 命令</param> /// <param name="conn">已经存在的数据库连接</param> /// <param name="trans">数据库事物处理</param> /// <param name="cmdType">SqlCommand命令类型 (存储过程， T-SQL语句， 等等。)</param> /// <param name="cmdText">Command text，T-SQL语句 例如 Select * from Products</param> /// <param name="cmdParms">返回带参数的命令</param> private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, CommandType cmdType, string cmdText, SqlParameter[] cmdParms) { //判断数据库连接状态 if (conn.State != ConnectionState.Open) conn.Open(); cmd.Connection = conn; cmd.CommandText = cmdText; //判断是否需要事物处理 if (trans != null) cmd.Transaction = trans; cmd.CommandType = cmdType; if (cmdParms != null) { foreach (SqlParameter parm in cmdParms) cmd.Parameters.Add(parm); } } /// <summary> /// 执行查询，返回结果集中的第一行第一列的值，忽略其他行列 /// </summary> /// <param name="sql"></param> /// <returns></returns> public static object ExcuteScalar(string sql) { using (SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction)) { con.Open(); SqlCommand cmd = new SqlCommand(sql, con); con.Close(); return cmd.ExecuteScalar(); } } /// <summary> /// 执行查询 /// </summary> /// <param name="sql">有效的sql语句</param> /// <param name="param">返回DataReader</param> /// <returns>返回DataReader</returns> public static SqlDataReader ExcuteReader(string sql, SqlParameter[] param) { SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction); con.Open(); SqlCommand cmd = new SqlCommand(sql, con); cmd.Parameters.AddRange(param); SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection); cmd.Parameters.Clear(); return reader; } /// <summary> /// 执行查询 /// </summary> /// <param name="sql">有效的sql语句</param> /// <returns>返回DataReader</returns> public static SqlDataReader ExcuteReader(string sql) { SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction); con.Open(); SqlCommand cmd = new SqlCommand(sql, con); return cmd.ExecuteReader(CommandBehavior.CloseConnection); } /// <summary> /// 执行查询的基方法 /// </summary> /// <param name="sql">有效的sql语句</param> /// <returns>返回DataTable</returns> public static DataTable ExcuteDataQuery(string sql) { using (SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction)) { con.Open(); SqlDataAdapter sda = new SqlDataAdapter(sql, con); DataTable table = new DataTable(); sda.Fill(table); con.Close(); return table; } } /// <summary> /// 执行增，删，改的基方法 /// </summary> /// <param name="sql">有效的sql语句</param> /// <param name="param">参数集合</param> /// <returns>影响的行数</returns> public static int ExcuteNonQuery(string sql, SqlParameter[] param) { using (SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction)) { con.Open(); SqlCommand cmd = new SqlCommand(sql, con); if (param != null) { cmd.Parameters.AddRange(param); } int count = cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); con.Close(); return count; } } //每页显示5条数据 static int pageSize = 10; /// <summary> /// 查询共有多少行，然后直接返回总页码 /// </summary> /// <returns></returns> public static int GetAllBookCount() { int num = 0; int pageCount = 0; string sql = "select count(0) from TB_BookInfo"; num = Convert.ToInt32(ExcuteScalar(sql)); pageCount = num % pageSize != 0 ? (num / pageSize) + 1 : num / pageSize; return pageCount; } /// <summary> /// 准备命令 /// </summary> /// <param name="con"></param> /// <param name="cmd"></param> /// <param name="textcmd"></param> /// <param name="cmdType"></param> /// <param name="param"></param> public static void PreparedCommd(SqlConnection con, SqlCommand cmd, string textcmd, CommandType cmdType, SqlParameter[] param) { try { if (con.State != ConnectionState.Open) { con.Open(); } cmd.Connection = con; cmd.CommandText = textcmd; cmd.CommandType = cmdType; if (param != null) { foreach (SqlParameter p in param) { cmd.Parameters.Add(p); } } } catch (Exception ex) { throw new Exception(ex.Message); } } /// <summary> /// 执行增、删、改 /// </summary> /// <param name="textcmd">sql语句或者存储过程</param> /// <param name="cmdType">类型</param> /// <param name="param">参数</param> /// <returns>返回int类型的数据</returns> public static int ExecuteNonQuery(string textcmd,SqlParameter[] param, CommandType cmdType) { using (SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction)) { SqlCommand cmd = new SqlCommand(); PreparedCommd(con, cmd, textcmd, cmdType, param); int num = cmd.ExecuteNonQuery(); return num; } } /// <summary> /// 读取一行一列的数据 /// </summary> /// <param name="textmd"></param> /// <param name="cmdType"></param> /// <param name="param"></param> /// <returns></returns> public static object ExecuteScalar(string textmd, CommandType cmdType, SqlParameter[] param) { using (SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction)) { SqlCommand cmd = new SqlCommand(); PreparedCommd(con, cmd, textmd, cmdType, param); return cmd.ExecuteScalar(); } } /// <summary> /// 读取一行一列的数据 /// </summary> /// <param name="textmd"></param> /// <param name="cmdType"></param> /// <param name="param"></param> /// <returns></returns> public static object ExecuteScalar(string SQL) { using (SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction)) { con.Open(); SqlCommand cmd = new SqlCommand(SQL, con); return cmd.ExecuteScalar(); } } /// <summary> /// 查询 /// </summary> /// <param name="textcmd"></param> /// <param name="cmdType"></param> /// <param name="param"></param> /// <returns></returns> public static SqlDataReader ExecuteReader(string textcmd, CommandType cmdType, SqlParameter[] param) { SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction); SqlCommand cmd = new SqlCommand(); try { //PreparedCommd(con, cmd, textcmd, cmdType, param); SqlDataReader read = cmd.ExecuteReader(CommandBehavior.CloseConnection); return read; } catch (Exception ex) { con.Close(); throw new Exception(ex.Message); } } /// <summary> /// 查询返回DataTable /// </summary> /// <param name="sql"></param> /// <returns></returns> public static DataTable ExecuteReader(string sql) { SqlConnection con = new SqlConnection(ConnectionStringLocalTransaction); DataTable dt = new DataTable(); try { SqlDataAdapter da = new SqlDataAdapter(sql, con); da.Fill(dt); } catch (Exception) { throw; } return dt; } /// <summary> /// 用户登录 /// </summary> /// <param name="UserName"></param> /// <param name="UserPwd"></param> /// <returns></returns> public static int CheckLogin(string UserName, string UserPwd) { int num = 0; try { string sql = "select * from TB_UserInfo where [user_Name]='" + UserName + "' and user_pwd='" + UserPwd + "'"; num = Convert.ToInt32(ExecuteScalar(sql)); } catch (Exception ex) { throw ex; } return num; } }
