//web.config页面 //OLDB数据访问类 /// Copyright (C) 2004-2008 LiTianPing /// 数据访问基础类(基于OleDb) /// 可以用户可以修改满足自己项目的需要。 /// public abstract class DbHelperOleDb { //数据库连接字符串(web.config来配置)，可以动态更改connectionString支持多数据库. public static string connectionString = ConfigurationManager.AppSettings["ConnectionString"].ToString() +HttpContext.Current.Server.MapPath(ConfigurationManager.AppSettings["dbPath"]) + ";"; public DbHelperOleDb() { }
using System; using System.Collections; using System.Collections.Specialized; using System.Data; using System.Data.OleDb; using System.Configuration; using System.Web; namespace OleDbHelp { /// /// Copyright (C) 2004-2008 LiTianPing /// 数据访问基础类(基于OleDb) /// 可以用户可以修改满足自己项目的需要。 /// public abstract class DbHelperOleDb { //数据库连接字符串(web.config来配置)，可以动态更改connectionString支持多数据库. public static string connectionString = ConfigurationManager.AppSettings["ConnectionString"].ToString() +HttpContext.Current.Server.MapPath(ConfigurationManager.AppSettings["dbPath"]) + ";"; public DbHelperOleDb() { } #region 公用方法 public static int GetMaxID(string FieldName, string TableName) { string strsql = "select max(" + FieldName + ")+1 from " + TableName; object obj = DbHelperOleDb.GetSingle(strsql); if (obj == null) { return 1; } else { return int.Parse(obj.ToString()); } } public static bool Exists(string strSql) { object obj = DbHelperOleDb.GetSingle(strSql); int cmdresult; if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) { cmdresult = 0; } else { cmdresult = int.Parse(obj.ToString()); } if (cmdresult == 0) { return false; } else { return true; } } public static bool Exists(string strSql, params OleDbParameter[] cmdParms) { object obj = GetSingle(strSql, cmdParms); int cmdresult; if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) { cmdresult = 0; } else { cmdresult = int.Parse(obj.ToString()); } if (cmdresult == 0) { return false; } else { return true; } } #endregion #region 执行简单SQL语句 /// /// 执行SQL语句，返回影响的记录数 /// /// SQL语句 /// 影响的记录数 public static int ExecuteSql(string SQLString) { using (OleDbConnection connection = new OleDbConnection(connectionString)) { using (OleDbCommand cmd = new OleDbCommand(SQLString, connection)) { try { connection.Open(); int rows = cmd.ExecuteNonQuery(); return rows; } catch (System.Data.OleDb.OleDbException E) { connection.Close(); throw new Exception(E.Message); } } } } /// /// 执行多条SQL语句，实现数据库事务。 /// /// 多条SQL语句 public static void ExecuteSqlTran(ArrayList SQLStringList) { using (OleDbConnection conn = new OleDbConnection(connectionString)) { conn.Open(); OleDbCommand cmd = new OleDbCommand(); cmd.Connection = conn; OleDbTransaction tx = conn.BeginTransaction(); cmd.Transaction = tx; try { for (int n = 0; n < SQLStringList.Count; n++) { string strsql = SQLStringList[n].ToString(); if (strsql.Trim().Length > 1) { cmd.CommandText = strsql; cmd.ExecuteNonQuery(); } } tx.Commit(); } catch (System.Data.OleDb.OleDbException E) { tx.Rollback(); throw new Exception(E.Message); } } } /// /// 执行带一个存储过程参数的的SQL语句。 /// /// SQL语句 /// 参数内容,比如一个字段是格式复杂的文章，有特殊符号，可以通过这个方式添加 /// 影响的记录数 public static int ExecuteSql(string SQLString, string content) { using (OleDbConnection connection = new OleDbConnection(connectionString)) { OleDbCommand cmd = new OleDbCommand(SQLString, connection); System.Data.OleDb.OleDbParameter myParameter = new System.Data.OleDb.OleDbParameter("@content", OleDbType.VarChar); myParameter.Value = content; cmd.Parameters.Add(myParameter); try { connection.Open(); int rows = cmd.ExecuteNonQuery(); return rows; } catch (System.Data.OleDb.OleDbException E) { throw new Exception(E.Message); } finally { cmd.Dispose(); connection.Close(); } } } /// /// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例) /// /// SQL语句 /// 图像字节,数据库的字段类型为image的情况 /// 影响的记录数 public static int ExecuteSqlInsertImg(string strSQL, byte[] fs) { using (OleDbConnection connection = new OleDbConnection(connectionString)) { OleDbCommand cmd = new OleDbCommand(strSQL, connection); System.Data.OleDb.OleDbParameter myParameter = new System.Data.OleDb.OleDbParameter("@fs", OleDbType.Binary); myParameter.Value = fs; cmd.Parameters.Add(myParameter); try { connection.Open(); int rows = cmd.ExecuteNonQuery(); return rows; } catch (System.Data.OleDb.OleDbException E) { throw new Exception(E.Message); } finally { cmd.Dispose(); connection.Close(); } } } /// /// 执行一条计算查询结果语句，返回查询结果（object）。 /// /// 计算查询结果语句 /// 查询结果（object） public static object GetSingle(string SQLString) { using (OleDbConnection connection = new OleDbConnection(connectionString)) { using (OleDbCommand cmd = new OleDbCommand(SQLString, connection)) { try { connection.Open(); object obj = cmd.ExecuteScalar(); if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) { return null; } else { return obj; } } catch (System.Data.OleDb.OleDbException e) { connection.Close(); throw new Exception(e.Message); } } } } /// /// 执行查询语句，返回OleDbDataReader /// /// 查询语句 /// OleDbDataReader public static OleDbDataReader ExecuteReader(string strSQL) { OleDbConnection connection = new OleDbConnection(connectionString); OleDbCommand cmd = new OleDbCommand(strSQL, connection); try { connection.Open(); OleDbDataReader myReader = cmd.ExecuteReader(); return myReader; } catch (System.Data.OleDb.OleDbException e) { throw new Exception(e.Message); } } /// /// 执行查询语句，返回DataSet /// /// 查询语句 /// DataSet public static DataSet Query(string SQLString) { using (OleDbConnection connection = new OleDbConnection(connectionString)) { DataSet ds = new DataSet(); try { connection.Open(); OleDbDataAdapter command = new OleDbDataAdapter(SQLString, connection); command.Fill(ds, "ds"); } catch (System.Data.OleDb.OleDbException ex) { throw new Exception(ex.Message); } return ds; } } #endregion #region 执行带参数的SQL语句 /// /// 执行SQL语句，返回影响的记录数 /// /// SQL语句 /// 影响的记录数 public static int ExecuteSql(string SQLString, params OleDbParameter[] cmdParms) { using (OleDbConnection connection = new OleDbConnection(connectionString)) { using (OleDbCommand cmd = new OleDbCommand()) { try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); int rows = cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); return rows; } catch (System.Data.OleDb.OleDbException E) { throw new Exception(E.Message); } } } } /// /// 执行多条SQL语句，实现数据库事务。 /// /// SQL语句的哈希表（key为sql语句，value是该语句的OleDbParameter[]） public static void ExecuteSqlTran(Hashtable SQLStringList) { using (OleDbConnection conn = new OleDbConnection(connectionString)) { conn.Open(); using (OleDbTransaction trans = conn.BeginTransaction()) { OleDbCommand cmd = new OleDbCommand(); try { //循环 foreach (DictionaryEntry myDE in SQLStringList) { string cmdText = myDE.Key.ToString(); OleDbParameter[] cmdParms = (OleDbParameter[])myDE.Value; PrepareCommand(cmd, conn, trans, cmdText, cmdParms); int val = cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); trans.Commit(); } } catch { trans.Rollback(); throw; } } } } /// /// 执行一条计算查询结果语句，返回查询结果（object）。 /// /// 计算查询结果语句 /// 查询结果（object） public static object GetSingle(string SQLString, params OleDbParameter[] cmdParms) { using (OleDbConnection connection = new OleDbConnection(connectionString)) { using (OleDbCommand cmd = new OleDbCommand()) { try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); object obj = cmd.ExecuteScalar(); cmd.Parameters.Clear(); if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) { return null; } else { return obj; } } catch (System.Data.OleDb.OleDbException e) { throw new Exception(e.Message); } } } } /// /// 执行查询语句，返回OleDbDataReader /// /// 查询语句 /// OleDbDataReader public static OleDbDataReader ExecuteReader(string SQLString, params OleDbParameter[] cmdParms) { OleDbConnection connection = new OleDbConnection(connectionString); OleDbCommand cmd = new OleDbCommand(); try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); OleDbDataReader myReader = cmd.ExecuteReader(); cmd.Parameters.Clear(); return myReader; } catch (System.Data.OleDb.OleDbException e) { throw new Exception(e.Message); } } /// /// 执行查询语句，返回DataSet /// /// 查询语句 /// DataSet public static DataSet Query(string SQLString, params OleDbParameter[] cmdParms) { using (OleDbConnection connection = new OleDbConnection(connectionString)) { OleDbCommand cmd = new OleDbCommand(); PrepareCommand(cmd, connection, null, SQLString, cmdParms); using (OleDbDataAdapter da = new OleDbDataAdapter(cmd)) { DataSet ds = new DataSet(); try { da.Fill(ds, "ds"); cmd.Parameters.Clear(); } catch (System.Data.OleDb.OleDbException ex) { throw new Exception(ex.Message); } return ds; } } } private static void PrepareCommand(OleDbCommand cmd, OleDbConnection conn, OleDbTransaction trans, string cmdText, OleDbParameter[] cmdParms) { if (conn.State != ConnectionState.Open) conn.Open(); cmd.Connection = conn; cmd.CommandText = cmdText; if (trans != null) cmd.Transaction = trans; cmd.CommandType = CommandType.Text;//cmdType; if (cmdParms != null) { foreach (OleDbParameter parm in cmdParms) cmd.Parameters.Add(parm); } } #endregion } }
