C#.NET universal database access encapsulation class (ACCESS, SQLServer, Oracle)

在app.config文件中写上数据库中连接信息：
<appSettings>
    <add key="connectionstring" value="Data Source=LocalHost;Initial Catalog=Test001;
    User ID=sa;Password=aaaaaa" />
    <add key="DataType" value="SqlServer" />
 </appSettings>
app.config文件中代码解析：
<appSettings>
    <add key="connectionstring" value="Data Source=你的数据库器（本机可用LocalHost,如果是EXPRESS开发版则必须是.\SQLEXPRESS);
    Initial Catalog=数据库名字;
    User ID=用户名;Password=你自己的密码" />
    <add key="TemplatePATH" value="Template" />
</appSettings>

Small note:

Similar to the web program, you can put the database connection information in web.config.

C#.NET universal database access encapsulation class code is as follows: (This code comes from Baidu Library, not written by myself)

<pre code_snippet_id="147172" snippet_file_name="blog_20140108_1_6139061" class="html" name="code">
<div><pre code_snippet_id="147172" snippet_file_name="blog_20140108_1_6139061" class="prettyprint" name="code">
<pre code_snippet_id="147172" snippet_file_name="blog_20140108_1_6139061" class="csharp" name="code">using System;  
using System.Linq;  
using System.Text;  
using System.Collections;  
using System.Collections.Specialized;  
using System.Data;  
using System.Data.SqlClient;  
using System.Data.OleDb;  
using System.Data.OracleClient;  
using System.Configuration;  
using System.Reflection;  
  
namespace SystemFramework.DAL  
{  
    class DataBaseLayer  
    {  
        #region  属性变量     
        private string connectionString;  
        public string ConntionString  
        {  
            get  
            {  
                return connectionString;  
            }  
            set  
            {  
                connectionString = value;  
            }  
        }  
        //数据访问基础类--构造函数  
        public DataBaseLayer(string strConnect, string dataType)  
        {  
            this.ConntionString = strConnect;  
            this.DbType = dataType;  
        }  
        //数据访问基础类--构造函数  
        public DataBaseLayer()  
        {  
            this.connectionString =ConfigurationManager.AppSettings["ConnectionString"];  
            this.dbType =ConfigurationManager.AppSettings["DataType"];  
            //也可以在代码中直接赋值  
            //this.connectionString = "data source=192.168.1.43;user id=sa;pwd=sa;database=temphrdb";  
            //this.dbType = "SqlServer";  
        }  
        /// <summary>  
        /// 数据库类型   
        /// </summary>  
        private string dbType;  
        public string DbType  
        {  
            get  
            {  
                if (string.IsNullOrEmpty(dbType))  
                {  
                    return "Access";  
                }  
                else  
                {  
                    return dbType;  
                }  
            }  
            set  
            {  
                if (value != string.Empty && value != null)  
                {  
                    dbType = value;  
                }  
                if (string.IsNullOrEmpty(dbType))  
                {  
                    dbType =ConfigurationManager.AppSettings["DataType"];  
                }  
                if (string.IsNullOrEmpty(dbType))  
                {  
                    dbType = "Access";  
                }  
            }  
        }  
        #endregion  
        #region 转换参数  
        private System.Data.IDbDataParameter iDbPara(string ParaName, string DataType)  
        {  
            switch (this.DbType)  
            {  
                case "SqlServer":  
                    return GetSqlPara(ParaName, DataType);  
                case "Oracle":  
                    return GetOleDbPara(ParaName, DataType);  
                case "Access":  
                    return GetOleDbPara(ParaName, DataType);  
                default:  
                    return GetSqlPara(ParaName, DataType);  
            }  
        }  
  
        private SqlParameter GetSqlPara(string ParaName, string DataType)  
        {  
            switch (DataType)  
            {  
                case "Decimal":  
                    return new SqlParameter(ParaName, SqlDbType.Decimal);  
                case "Varchar":  
                    return new SqlParameter(ParaName, SqlDbType.VarChar);  
                case "DateTime":  
                    return new SqlParameter(ParaName, SqlDbType.DateTime);  
                case "Iamge":  
                    return new SqlParameter(ParaName, SqlDbType.Image);  
                case "Int":  
                    return new SqlParameter(ParaName, SqlDbType.Int);  
                case "Text":  
                    return new SqlParameter(ParaName, SqlDbType.NText);  
                default:  
                    return new SqlParameter(ParaName, SqlDbType.VarChar);  
            }  
        }  
        private OracleParameter GetOraclePara(string ParaName, string DataType)  
        {  
            switch (DataType)  
            {  
                case "Decimal":  
                    return new OracleParameter(ParaName, OracleType.Double);  
                case "Varchar":  
                    return new OracleParameter(ParaName, OracleType.VarChar);  
                case "DateTime":  
                   return new OracleParameter(ParaName, OracleType.DateTime);  
                case "Iamge":  
                    return new OracleParameter(ParaName, OracleType.BFile);  
                case "Int":  
                    return new OracleParameter(ParaName, OracleType.Int32);  
                case "Text":  
                    return new OracleParameter(ParaName, OracleType.LongVarChar);  
                default:  
                    return new OracleParameter(ParaName, OracleType.VarChar);  
  
            }  
        }  
        private OleDbParameter GetOleDbPara(string ParaName, string DataType)  
        {  
            switch (DataType)  
            {  
                case "Decimal":  
                    return new OleDbParameter(ParaName, System.Data.DbType.Decimal);  
                case "Varchar":  
                    return new OleDbParameter(ParaName, System.Data.DbType.String);  
                case "DateTime":  
                    return new OleDbParameter(ParaName, System.Data.DbType.DateTime);  
                case "Iamge":  
                    return new OleDbParameter(ParaName, System.Data.DbType.Binary);  
                case "Int":  
                    return new OleDbParameter(ParaName, System.Data.DbType.Int32);  
                case "Text":  
                    return new OleDbParameter(ParaName, System.Data.DbType.String);  
                default:  
                    return new OleDbParameter(ParaName, System.Data.DbType.String);  
            }  
        }  
        #endregion  
        #region 创建 Connection 和 Command  
        private IDbConnection GetConnection()  
        {  
            switch (this.DbType)  
            {  
                case "SqlServer":  
                    return new SqlConnection(this.ConntionString);  
                case "Oracle":  
                    return new OracleConnection(this.ConntionString);  
                case "Access":  
                    return new OleDbConnection(this.ConntionString);  
                default:  
                    return new SqlConnection(this.ConntionString);  
            }  
        }  
        private IDbCommand GetCommand(string Sql, IDbConnection iConn)  
        {  
            switch (this.DbType)  
            {  
                case "SqlServer":  
                    return new SqlCommand(Sql, (SqlConnection)iConn);  
                case "Oracle":  
                    return new OracleCommand(Sql, (OracleConnection)iConn);  
                case "Access":  
                    return new OleDbCommand(Sql, (OleDbConnection)iConn);  
                default:  
                    return new SqlCommand(Sql, (SqlConnection)iConn);  
            }  
        }  
        private IDbCommand GetCommand()  
        {  
            switch (this.DbType)  
            {  
                case "SqlServer":  
                    return new SqlCommand();  
                case "Oracle":  
                    return new OracleCommand();  
                case "Access":  
                    return new OleDbCommand();  
                default:  
                    return new SqlCommand();  
            }  
        }  
        private IDataAdapter GetAdapater(string Sql, IDbConnection iConn)  
        {  
            switch (this.DbType)  
            {  
                case "SqlServer":  
                    return new SqlDataAdapter(Sql, (SqlConnection)iConn);  
                case "Oracle":  
                    return new OracleDataAdapter(Sql, (OracleConnection)iConn);  
                case "Access":  
                    return new OleDbDataAdapter(Sql, (OleDbConnection)iConn);  
                default:  
                    return new SqlDataAdapter(Sql, (SqlConnection)iConn); ;  
            }  
        }  
        private IDataAdapter GetAdapater()  
        {  
            switch (this.DbType)  
            {  
                case "SqlServer":  
                    return new SqlDataAdapter();  
                case "Oracle":  
                    return new OracleDataAdapter();  
                case "Access":  
                    return new OleDbDataAdapter();  
                default:  
                    return new SqlDataAdapter();  
            }  
        }  
        private IDataAdapter GetAdapater(IDbCommand iCmd)  
        {  
            switch (this.DbType)  
            {  
                case "SqlServer":  
                    return new SqlDataAdapter((SqlCommand)iCmd);  
                case "Oracle":  
                    return new OracleDataAdapter((OracleCommand)iCmd);  
                case "Access":  
                    return new OleDbDataAdapter((OleDbCommand)iCmd);  
                default:  
                    return new SqlDataAdapter((SqlCommand)iCmd);  
            }  
        }  
        #endregion  
        #region  执行简单SQL语句  
        /// <summary>  
        /// 执行SQL语句，返回影响的记录数  
        /// </summary>  
        /// <param name="SQLString">SQL语句</param>  
        /// <returns>影响的记录数</returns>  
        public int ExecuteSql(string SqlString)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                using (IDbCommand iCmd = GetCommand(SqlString, iConn))  
                {  
                    iConn.Open();  
                    try  
                    {  
                        int rows = iCmd.ExecuteNonQuery();  
                        return rows;  
                    }  
                    catch (System.Exception E)  
                    {  
                        throw new Exception(E.Message);  
                    }  
                    finally  
                    {  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行多条SQL语句，实现数据库事务。  
        /// </summary>  
        /// <param name="SQLStringList">多条SQL语句</param>          
        public void ExecuteSqlTran(ArrayList SQLStringList)  
        {  
            //using作为语句，用于定义一个范围，在此范围的末尾将释放对象  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                iConn.Open();  
                using (IDbCommand iCmd = GetCommand())  
                {  
                    iCmd.Connection = iConn;  
                    using (System.Data.IDbTransaction iDbTran = iConn.BeginTransaction())  
                    {  
                        iCmd.Transaction = iDbTran;  
                        try  
                        {  
                            for (int n = 0; n < SQLStringList.Count; n++)  
                            {  
                                string strsql = SQLStringList[n].ToString();  
                                if (strsql.Trim().Length > 1)  
                                {  
                                    iCmd.CommandText = strsql;  
                                    iCmd.ExecuteNonQuery();  
                                }  
                            }  
                            iDbTran.Commit();  
                        }  
                        catch (System.Exception E)  
                        {  
                            iDbTran.Rollback();  
                            throw new Exception(E.Message);  
                        }  
                        finally  
                        {  
                            if (iConn.State != ConnectionState.Closed)  
                            {  
                                iConn.Close();  
                            }  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行带一个存储过程参数的的SQL语句。  
        /// </summary>  
        /// <param name="SQLString">SQL语句</param>  
        /// <param name="content">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</param>  
        /// <returns>影响的记录数</returns>  
        public int ExecuteSql(string SqlString, string content)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                using (IDbCommand iCmd = GetCommand(SqlString, iConn))  
                {  
                    IDataParameter myParameter = this.iDbPara("@content", "Text");  
                    myParameter.Value = content;  
                    iCmd.Parameters.Add(myParameter);  
                    iConn.Open();  
                    try  
                    {  
                        int rows = iCmd.ExecuteNonQuery();  
                        return rows;  
                    }  
                    catch (System.Exception e)  
                    {  
                        throw new Exception(e.Message);  
                    }  
                    finally  
                    {  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 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)  
        /// </summary>  
        /// <param name="strSQL">SQL语句</param>  
        /// <param name="fs">图像字节,数据库的字段类型为image的情况</param>  
        /// <returns>影响的记录数</returns>  
        public int ExecuteSqlInsertImg(string SqlString, byte[] fs)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                using (IDbCommand iCmd = GetCommand(SqlString, iConn))  
                {  
                    IDataParameter myParameter = this.iDbPara("@content", "Image");  
                    myParameter.Value = fs;  
                    iCmd.Parameters.Add(myParameter);  
                    iConn.Open();  
                    try  
                    {  
                        int rows = iCmd.ExecuteNonQuery();  
                        return rows;  
                    }  
                    catch (System.Exception e)  
                    {  
                        throw new Exception(e.Message);  
                    }  
                    finally  
                    {  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行一条计算查询结果语句，返回查询结果（object）。  
        /// </summary>  
        /// <param name="SQLString">计算查询结果语句</param>  
        /// <returns>查询结果（object）</returns>  
        public object GetSingle(string SqlString)  
        {  
            using (IDbConnection iConn = GetConnection())  
            {  
                using (IDbCommand iCmd = GetCommand(SqlString, iConn))  
                {  
                    iConn.Open();  
                    try  
                    {  
                        object obj = iCmd.ExecuteScalar();  
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))  
                        {  
                            return null;  
                        }  
                        else  
                        {  
                            return obj;  
                        }  
                    }  
                    catch (System.Exception e)  
                    {  
                        throw new Exception(e.Message);  
                    }  
                    finally  
                    {  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }       
        /// <summary>  
        /// 执行查询语句，返回IDataAdapter  
        /// </summary>  
        /// <param name="strSQL">查询语句</param>  
        /// <returns>IDataAdapter</returns>  
        public IDataAdapter ExecuteReader(string strSQL)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                iConn.Open();  
                try  
                {  
                    IDataAdapter iAdapter = this.GetAdapater(strSQL, iConn);  
                    return iAdapter;  
                }  
                catch (System.Exception e)  
                {  
                    throw new Exception(e.Message);  
                }  
                finally  
                {  
                    if (iConn.State != ConnectionState.Closed)  
                    {  
                        iConn.Close();  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行查询语句，返回DataSet  
        /// </summary>  
        /// <param name="SQLString">查询语句</param>  
        /// <returns>DataSet</returns>  
        public DataSet Query(string sqlString)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                using (IDbCommand iCmd = GetCommand(sqlString, iConn))  
                {  
                    DataSet ds = new DataSet();  
                    iConn.Open();  
                    try  
                    {  
                        IDataAdapter iAdapter = this.GetAdapater(sqlString, iConn);  
                        iAdapter.Fill(ds);  
                        return ds;  
                    }  
                    catch (System.Exception ex)  
                    {  
                        throw new Exception(ex.Message);  
                    }  
                    finally  
                    {  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行查询语句，返回DataSet  
        /// </summary>  
        /// <param name="sqlString">查询语句</param>  
        /// <param name="dataSet">要填充的DataSet</param>  
        /// <param name="tableName">要填充的表名</param>  
        /// <returns>DataSet</returns>  
        public DataSet Query(string sqlString, DataSet dataSet, string tableName)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                using (IDbCommand iCmd = GetCommand(sqlString, iConn))  
                {  
                    iConn.Open();  
                    try  
                    {  
                        IDataAdapter iAdapter = this.GetAdapater(sqlString, iConn);  
                        ((OleDbDataAdapter)iAdapter).Fill(dataSet, tableName);  
                        return dataSet;  
                    }  
                    catch (System.Exception ex)  
                    {  
                        throw new Exception(ex.Message);  
                    }  
                    finally  
                    {  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行SQL语句 返回存储过程  
        /// </summary>  
        /// <param name="sqlString">Sql语句</param>  
        /// <param name="dataSet">要填充的DataSet</param>  
        /// <param name="startIndex">开始记录</param>  
        /// <param name="pageSize">页面记录大小</param>  
        /// <param name="tableName">表名称</param>  
        /// <returns>DataSet</returns>  
        public DataSet Query(string sqlString, DataSet dataSet, int startIndex, int pageSize, string tableName)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                iConn.Open();  
                try  
                {  
                    IDataAdapter iAdapter = this.GetAdapater(sqlString, iConn);  
  
                    ((OleDbDataAdapter)iAdapter).Fill(dataSet, startIndex, pageSize, tableName);  
  
                    return dataSet;  
                }  
                catch (Exception ex)  
                {  
                    throw new Exception(ex.Message);  
                }  
                finally  
                {  
                    if (iConn.State != ConnectionState.Closed)  
                    {  
                        iConn.Close();  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行查询语句，向XML文件写入数据  
        /// </summary>  
        /// <param name="sqlString">查询语句</param>  
        /// <param name="xmlPath">XML文件路径</param>  
        public void WriteToXml(string sqlString, string xmlPath)  
        {  
            Query(sqlString).WriteXml(xmlPath);  
        }  
        /// <summary>  
        /// 执行查询语句  
        /// </summary>  
        /// <param name="SqlString">查询语句</param>  
        /// <returns>DataTable </returns>  
        public DataTable ExecuteQuery(string sqlString)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                //IDbCommand iCmd  =  GetCommand(sqlString,iConn);  
                DataSet ds = new DataSet();  
                try  
                {  
                    IDataAdapter iAdapter = this.GetAdapater(sqlString, iConn);  
                    iAdapter.Fill(ds);  
                }  
                catch (System.Exception e)  
                {  
                    throw new Exception(e.Message);  
                }  
                finally  
                {  
                    if (iConn.State != ConnectionState.Closed)  
                    {  
                        iConn.Close();  
                    }  
                }  
                return ds.Tables[0];  
            }  
        }  
        /// <summary>  
        /// 执行查询语句  
        /// </summary>  
        /// <param name="SqlString">查询语句</param>  
        /// <returns>DataTable </returns>  
        public DataTable ExecuteQuery(string SqlString, string Proc)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                using (IDbCommand iCmd = GetCommand(SqlString, iConn))  
                {  
                    iCmd.CommandType = CommandType.StoredProcedure;  
                    DataSet ds = new DataSet();  
                    try  
                    {  
                        IDataAdapter iDataAdapter = this.GetAdapater(SqlString, iConn);  
                        iDataAdapter.Fill(ds);  
                    }  
                    catch (System.Exception e)  
                    {  
                        throw new Exception(e.Message);  
                    }  
                    finally  
                    {  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                    return ds.Tables[0];  
                }  
            }  
        }  
        /// <summary>  
        /// 执行查询，并以DataView返回结果集   
        /// </summary>  
        /// <param name="Sql">SQL语句</param>  
        /// <returns>DataView</returns>  
        public DataView ExeceuteDataView(string Sql)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                using (IDbCommand iCmd = GetCommand(Sql, iConn))  
                {  
                    DataSet ds = new DataSet();  
                    try  
                    {  
                        IDataAdapter iDataAdapter = this.GetAdapater(Sql, iConn);  
                        iDataAdapter.Fill(ds);  
                        return ds.Tables[0].DefaultView;  
                    }  
                    catch (System.Exception e)  
                    {  
                        throw new Exception(e.Message);  
                    }  
                    finally  
                    {  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        #endregion  
        #region 执行带参数的SQL语句  
        /// <summary>  
        /// 执行SQL语句，返回影响的记录数  
        /// </summary>  
        /// <param name="SQLString">SQL语句</param>  
        /// <returns>影响的记录数</returns>  
        public int ExecuteSql(string SQLString, params IDataParameter[] iParms)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                IDbCommand iCmd = GetCommand();  
                {  
                    try  
                    {  
                        PrepareCommand(out iCmd, iConn, null, SQLString, iParms);  
                        int rows = iCmd.ExecuteNonQuery();  
                        iCmd.Parameters.Clear();  
                        return rows;  
                    }  
                    catch (System.Exception E)  
                    {  
                        throw new Exception(E.Message);  
                    }  
                    finally  
                    {  
                        iCmd.Dispose();  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行多条SQL语句，实现数据库事务。  
        /// </summary>  
        /// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]）</param>  
        public void ExecuteSqlTran(Hashtable SQLStringList)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                iConn.Open();  
                using (IDbTransaction iTrans = iConn.BeginTransaction())  
                {  
                    IDbCommand iCmd = GetCommand();  
                    try  
                    {  
                        //循环  
                        foreach (DictionaryEntry myDE in SQLStringList)  
                        {  
                            string cmdText = myDE.Key.ToString();  
                            IDataParameter[] iParms = (IDataParameter[])myDE.Value;  
                            PrepareCommand(out iCmd, iConn, iTrans, cmdText, iParms);  
                            int val = iCmd.ExecuteNonQuery();  
                            iCmd.Parameters.Clear();  
                        }  
                        iTrans.Commit();  
                    }  
                    catch  
                    {  
                        iTrans.Rollback();  
                        throw;  
                    }  
                    finally  
                    {  
                        iCmd.Dispose();  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行一条计算查询结果语句，返回查询结果（object）。  
        /// </summary>  
        /// <param name="SQLString">计算查询结果语句</param>  
        /// <returns>查询结果（object）</returns>  
        public object GetSingle(string SQLString, params IDataParameter[] iParms)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                IDbCommand iCmd = GetCommand();  
                {  
                    try  
                    {  
                        PrepareCommand(out iCmd, iConn, null, SQLString, iParms);  
                        object obj = iCmd.ExecuteScalar();  
                        iCmd.Parameters.Clear();  
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))  
                        {  
                            return null;  
                        }  
                        else  
                        {  
                            return obj;  
                        }  
                    }  
                    catch (System.Exception e)  
                    {  
                        throw new Exception(e.Message);  
                    }  
                    finally  
                    {  
                        iCmd.Dispose();  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行查询语句，返回IDataReader  
        /// </summary>  
        /// <param name="strSQL">查询语句</param>  
        /// <returns> IDataReader </returns>  
        public IDataReader ExecuteReader(string SQLString, params IDataParameter[] iParms)  
        {  
            IDbConnection iConn = this.GetConnection();  
            {  
                IDbCommand iCmd = GetCommand();  
                {  
                    try  
                    {  
                        PrepareCommand(out iCmd, iConn, null, SQLString, iParms);  
                        System.Data.IDataReader iReader = iCmd.ExecuteReader();  
                        iCmd.Parameters.Clear();  
                        return iReader;  
                    }  
                    catch (System.Exception e)  
                    {  
                        throw new Exception(e.Message);  
                    }  
                    finally  
                    {  
                        iCmd.Dispose();  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 执行查询语句，返回DataSet  
        /// </summary>  
        /// <param name="SQLString">查询语句</param>  
        /// <returns>DataSet</returns>  
        public DataSet Query(string sqlString, params IDataParameter[] iParms)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                IDbCommand iCmd = GetCommand();  
                {  
                    PrepareCommand(out iCmd, iConn, null, sqlString, iParms);  
                    try  
                    {  
                        IDataAdapter iAdapter = this.GetAdapater(sqlString, iConn);  
                        DataSet ds = new DataSet();  
                        iAdapter.Fill(ds);  
                        iCmd.Parameters.Clear();  
                        return ds;  
                    }  
                    catch (System.Exception ex)  
                    {  
                        throw new Exception(ex.Message);  
                    }  
                    finally  
                    {  
                        iCmd.Dispose();  
                        if (iConn.State != ConnectionState.Closed)  
                        {  
                            iConn.Close();  
                        }  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 初始化Command  
        /// </summary>  
        /// <param name="iCmd"></param>  
        /// <param name="iConn"></param>  
        /// <param name="iTrans"></param>  
        /// <param name="cmdText"></param>  
        /// <param name="iParms"></param>  
        private void PrepareCommand(out IDbCommand iCmd, IDbConnection iConn, System.Data.IDbTransaction iTrans, string cmdText, IDataParameter[] iParms)  
        {  
            if (iConn.State != ConnectionState.Open)  
                iConn.Open();  
            iCmd = this.GetCommand();  
            iCmd.Connection = iConn;  
            iCmd.CommandText = cmdText;  
            if (iTrans != null)  
                iCmd.Transaction = iTrans;  
            iCmd.CommandType = CommandType.Text;//cmdType;  
            if (iParms != null)  
            {  
                foreach (IDataParameter parm in iParms)  
                    iCmd.Parameters.Add(parm);  
            }  
        }  
        #endregion  
        #region 存储过程操作  
        /// <summary>  
        /// 执行存储过程  
        /// </summary>  
        /// <param name="storedProcName">存储过程名</param>  
        /// <param name="parameters">存储过程参数</param>  
        /// <returns>SqlDataReader</returns>  
        public SqlDataReader RunProcedure(string storedProcName, IDataParameter[] parameters)  
        {  
            IDbConnection iConn = this.GetConnection();  
            {  
                iConn.Open();  
  
                using (SqlCommand sqlCmd = BuildQueryCommand(iConn, storedProcName, parameters))  
                {  
                    return sqlCmd.ExecuteReader(CommandBehavior.CloseConnection);  
                }  
            }  
        }  
        /// <summary>  
        /// 执行存储过程  
        /// </summary>  
        /// <param name="storedProcName">存储过程名</param>  
        /// <param name="parameters">存储过程参数</param>  
        /// <param name="tableName">DataSet结果中的表名</param>  
        /// <returns>DataSet</returns>  
        public DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, string tableName)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                DataSet dataSet = new DataSet();  
                iConn.Open();  
                IDataAdapter iDA = this.GetAdapater();  
                iDA = this.GetAdapater(BuildQueryCommand(iConn, storedProcName, parameters));  
                ((SqlDataAdapter)iDA).Fill(dataSet, tableName);  
                if (iConn.State != ConnectionState.Closed)  
                {  
                    iConn.Close();  
                }  
                return dataSet;  
            }  
        }  
        /// <summary>  
        /// 执行存储过程  
        /// </summary>  
        /// <param name="storedProcName">存储过程名</param>  
        /// <param name="parameters">存储过程参数</param>  
        /// <param name="tableName">DataSet结果中的表名</param>  
        /// <param name="startIndex">开始记录索引</param>  
        /// <param name="pageSize">页面记录大小</param>  
        /// <returns>DataSet</returns>  
        public DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, int startIndex, int pageSize, string tableName)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                DataSet dataSet = new DataSet();  
                iConn.Open();  
                IDataAdapter iDA = this.GetAdapater();  
                iDA = this.GetAdapater(BuildQueryCommand(iConn, storedProcName, parameters));  
  
                ((SqlDataAdapter)iDA).Fill(dataSet, startIndex, pageSize, tableName);  
                if (iConn.State != ConnectionState.Closed)  
                {  
                    iConn.Close();  
                }  
                return dataSet;  
            }  
        }  
        /// <summary>  
        /// 执行存储过程 填充已经存在的DataSet数据集   
        /// </summary>  
        /// <param name="storeProcName">存储过程名称</param>  
        /// <param name="parameters">存储过程参数</param>  
        /// <param name="dataSet">要填充的数据集</param>  
        /// <param name="tablename">要填充的表名</param>  
        /// <returns></returns>  
        public DataSet RunProcedure(string storeProcName, IDataParameter[] parameters, DataSet dataSet, string tableName)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                iConn.Open();  
                IDataAdapter iDA = this.GetAdapater();  
                iDA = this.GetAdapater(BuildQueryCommand(iConn, storeProcName, parameters));  
  
                ((SqlDataAdapter)iDA).Fill(dataSet, tableName);  
  
                if (iConn.State != ConnectionState.Closed)  
                {  
                    iConn.Close();  
                }  
                return dataSet;  
            }  
        }  
        /// <summary>  
        /// 执行存储过程并返回受影响的行数  
        /// </summary>  
        /// <param name="storedProcName"></param>  
        /// <param name="parameters"></param>  
        /// <returns></returns>  
        public int RunProcedureNoQuery(string storedProcName, IDataParameter[] parameters)  
        {  
            int result = 0;  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                iConn.Open();  
                using (SqlCommand scmd = BuildQueryCommand(iConn, storedProcName, parameters))  
                {  
                    result = scmd.ExecuteNonQuery();  
                }  
  
                if (iConn.State != ConnectionState.Closed)  
                {  
                    iConn.Close();  
                }  
            }  
            return result;  
        }  
        public string RunProcedureExecuteScalar(string storeProcName, IDataParameter[] parameters)  
        {  
            string result = string.Empty;  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                iConn.Open();  
                using (SqlCommand scmd = BuildQueryCommand(iConn, storeProcName, parameters))  
                {  
                    object obj = scmd.ExecuteScalar();  
                    if (obj == null)  
                        result = null;  
                    else  
                        result = obj.ToString();  
                }  
                if (iConn.State != ConnectionState.Closed)  
                {  
                    iConn.Close();  
                }  
            }  
            return result;  
        }  
        /// <summary>  
        /// 构建 SqlCommand 对象(用来返回一个结果集，而不是一个整数值)  
        /// </summary>  
        /// <param name="connection">数据库连接</param>  
        /// <param name="storedProcName">存储过程名</param>  
        /// <param name="parameters">存储过程参数</param>  
        /// <returns>SqlCommand</returns>  
        private SqlCommand BuildQueryCommand(IDbConnection iConn, string storedProcName, IDataParameter[] parameters)  
        {  
            IDbCommand iCmd = GetCommand(storedProcName, iConn);  
            iCmd.CommandType = CommandType.StoredProcedure;  
            if (parameters == null)  
            {  
                return (SqlCommand)iCmd;  
            }  
            foreach (IDataParameter parameter in parameters)  
            {  
                iCmd.Parameters.Add(parameter);  
            }  
            return (SqlCommand)iCmd;  
        }  
        /// <summary>  
        /// 执行存储过程，返回影响的行数          
        /// </summary>  
        /// <param name="storedProcName">存储过程名</param>  
        /// <param name="parameters">存储过程参数</param>  
        /// <param name="rowsAffected">影响的行数</param>  
        /// <returns></returns>  
        public int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected)  
        {  
            using (IDbConnection iConn = this.GetConnection())  
            {  
                int result;  
                iConn.Open();  
                using (SqlCommand sqlCmd = BuildIntCommand(iConn, storedProcName, parameters))  
                {  
                    rowsAffected = sqlCmd.ExecuteNonQuery();  
                    result = (int)sqlCmd.Parameters["ReturnValue"].Value;  
                    if (iConn.State != ConnectionState.Closed)  
                    {  
                        iConn.Close();  
                    }  
                    return result;  
                }  
            }  
        }  
        /// <summary>  
        /// 创建 SqlCommand 对象实例(用来返回一个整数值)      
        /// </summary>  
        /// <param name="storedProcName">存储过程名</param>  
        /// <param name="parameters">存储过程参数</param>  
        /// <returns>SqlCommand 对象实例</returns>  
        private SqlCommand BuildIntCommand(IDbConnection iConn, string storedProcName, IDataParameter[] parameters)  
        {  
            SqlCommand sqlCmd = BuildQueryCommand(iConn, storedProcName, parameters);  
            sqlCmd.Parameters.Add(new SqlParameter("ReturnValue",  
                SqlDbType.Int, 4, ParameterDirection.ReturnValue,  
                false, 0, 0, string.Empty, DataRowVersion.Default, null));  
            return sqlCmd;  
        }  
        #endregion  
    }  
}

小注：