以前通用的数据访问会写工厂方法，又一次看到这种写法，觉得很不错，至少一个类就解决问题了，不用什么接口了实现了的！代码当然也是从别人那借鉴过来修改的，也不知道原作者是谁了。
//******************************************************************/
//类名:ADO数据库帮助类
//描述:ADO方式的数据库增删改查，支持事务，存储过程，支持多类型数据库
//作者:zhahost
//时间:2010-06-24
//******************************************************************/
using System;
using System.Collections;
using System.Collections.Specialized;
using System.Data;
using System.Configuration;
using System.Data.Common;
namespace RV.DataAccess
{
/// <summary>
/// ADO数据库帮助类
/// </summary>
public class DBHelper
{
#region 变量定义
protected string DBConnectionString;
protected DbProviderFactory DBProvider;
protected static string DefaultDB = ConfigurationManager.AppSettings["DefaultDB"];
#endregion
#region 构造函数
private DBHelper() { }
#endregion
#region 帮助类实例
/// <summary>
/// 默认DefaultDB帮助类实例
/// </summary>
/// <returns>帮助类实例</returns>
public static DBHelper Instance()
{
return Instance(DefaultDB);
}
/// <summary>
/// 指定数据库的帮助类实例
/// </summary>
/// <param name="DBKey">数据库标识符</param>
/// <returns>帮助类实例</returns>
public static DBHelper Instance(string DBKey)
{
DBHelper helper = new DBHelper();
helper.DBConnectionString = ConfigurationManager.ConnectionStrings[DBKey].ConnectionString;
helper.DBProvider = DbProviderFactories.GetFactory(ConfigurationManager.ConnectionStrings[DBKey].ProviderName);
return helper;
}
#endregion
#region 辅助方法
private DbCommand BuildQueryCommand(DbConnection conn, string storedProcName, DbParameter[] parameters)
{
if (conn.State != ConnectionState.Open)
{
conn.Open();
}
DbCommand cmd = DBProvider.CreateCommand();
cmd.CommandText = storedProcName;
cmd.Connection = conn;
cmd.CommandType = CommandType.StoredProcedure;
if (parameters != null)
{
foreach (DbParameter parameter in parameters)
{
cmd.Parameters.Add(parameter);
}
}
return cmd;
}
private void PrepareCommand(DbCommand cmd, DbConnection conn, DbTransaction trans, string cmdText, DbParameter[] 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 (DbParameter parm in cmdParms)
{
cmd.Parameters.Add(parm);
}
}
}
#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 ExecuteNonQuery(string SQLString)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
using (DbCommand cmd = DBProvider.CreateCommand())
{
cmd.Connection = conn;
cmd.CommandText = SQLString;
try
{
conn.Open();
int rows = cmd.ExecuteNonQuery();
return rows;
}
catch (DbException E)
{
conn.Close();
conn.Dispose();
throw new Exception(E.Message);
}
}
}
}
/// <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 (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
conn.Open();
using (DbCommand cmd = DBProvider.CreateCommand())
{
cmd.Connection = conn;
using (DbTransaction 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 (DbException ex)
{
tx.Rollback();
conn.Close();
conn.Dispose();
throw ex;
}
}
}
}
}
/// <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 ExecuteScalar(string SQLString)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
using (DbCommand cmd = DBProvider.CreateCommand())
{
cmd.Connection = conn;
cmd.CommandText = SQLString;
try
{
conn.Open();
object obj = cmd.ExecuteScalar();
if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch (DbException e)
{
conn.Close();
conn.Dispose();
throw new Exception(e.Message);
}
}
}
}
/// <summary>
/// 执行查询语句，返回SqlDataReader
/// </summary>
/// <param name="strSQL">查询语句</param>
/// <returns>SqlDataReader</returns>
public DbDataReader ExecuteReader(string strSQL)
{
DbConnection conn = DBProvider.CreateConnection();
conn.ConnectionString = DBConnectionString;
DbCommand cmd = DBProvider.CreateCommand();
cmd.Connection = conn;
cmd.CommandText = strSQL;
try
{
conn.Open();
DbDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
return myReader;
}
catch (System.Data.Common.DbException e)
{
conn.Close();
conn.Dispose();
throw new Exception(e.Message);
}
}
/// <summary>
/// 执行查询语句，返回DataSet
/// </summary>
/// <param name="SQLString">查询语句</param>
/// <returns>DataSet</returns>
public DataSet ExecuteQuery(string SQLString)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
using (DbCommand cmd = DBProvider.CreateCommand())
{
cmd.Connection = conn;
cmd.CommandText = SQLString;
try
{
DataSet ds = new DataSet();
DbDataAdapter adapter = DBProvider.CreateDataAdapter();
adapter.SelectCommand = cmd;
adapter.Fill(ds, "ds");
return ds;
}
catch (DbException ex)
{
conn.Close();
conn.Dispose();
throw new Exception(ex.Message);
}
}
}
}
#endregion
#region 执行复杂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 ExecuteNonQuery(string SQLString, DbParameter[] cmdParms)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
using (DbCommand cmd = DBProvider.CreateCommand())
{
cmd.Connection = conn;
cmd.CommandText = SQLString;
try
{
PrepareCommand(cmd, conn, null, SQLString, cmdParms);
int rows = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return rows;
}
catch (DbException E)
{
conn.Close();
conn.Dispose();
throw new Exception(E.Message);
}
}
}
}
/// <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 (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
conn.Open();
using (DbTransaction trans = conn.BeginTransaction())
{
using (DbCommand cmd = DBProvider.CreateCommand())
{
try
{
//循环
foreach (DictionaryEntry myDE in SQLStringList)
{
string cmdText = myDE.Key.ToString();
DbParameter[] cmdParms = (DbParameter[])myDE.Value;
PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
}
trans.Commit();
}
catch (DbException ex)
{
trans.Rollback();
conn.Close();
conn.Dispose();
throw ex;
}
}
}
}
}
/// <summary>
/// 执行一条计算查询结果语句，返回查询结果（object）,返回首行首列的值;
/// </summary>
/// <param name="SQLString">计算查询结果语句</param>
/// <returns>查询结果（object）</returns>
public object ExecuteScalar(string SQLString, DbParameter[] cmdParms)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
using (DbCommand cmd = DBProvider.CreateCommand())
{
try
{
PrepareCommand(cmd, conn, 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 (DbException e)
{
conn.Close();
conn.Dispose();
throw new Exception(e.Message);
}
}
}
}
/// <summary>
/// 执行查询语句，返回SqlDataReader
/// </summary>
/// <param name="strSQL">查询语句</param>
/// <returns>SqlDataReader</returns>
public DbDataReader ExecuteReader(string SQLString, DbParameter[] cmdParms)
{
DbConnection conn = DBProvider.CreateConnection();
conn.ConnectionString = DBConnectionString;
DbCommand cmd = DBProvider.CreateCommand();
try
{
PrepareCommand(cmd, conn, null, SQLString, cmdParms);
DbDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return myReader;
}
catch (DbException e)
{
conn.Close();
conn.Dispose();
throw new Exception(e.Message);
}
}
/// <summary>
/// 执行查询语句，返回DataSet
/// </summary>
/// <param name="SQLString">查询语句</param>
/// <returns>DataSet</returns>
public DataSet ExecuteQuery(string SQLString, DbParameter[] cmdParms)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
using (DbCommand cmd = DBProvider.CreateCommand())
{
using (DbDataAdapter da = DBProvider.CreateDataAdapter())
{
PrepareCommand(cmd, conn, null, SQLString, cmdParms);
da.SelectCommand = cmd;
DataSet ds = new DataSet();
try
{
da.Fill(ds, "ds");
cmd.Parameters.Clear();
return ds;
}
catch (DbException ex)
{
conn.Close();
conn.Dispose();
throw new Exception(ex.Message);
}
}
}
}
}
#endregion
#region 更新数据集
/// <summary>
/// 使用DbCommandBuilder对单表的增删改,
/// 请注意DataSet.HasChanges()是否为true;
/// </summary>
/// <param name="tableNmae">表名</param>
/// <param name="ds">被修改过的数据源</param>
/// <returns>操作所影响的记录行</returns>
public int UpdateDataset(string tableNmae, DataSet ds)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
using (DbCommand cmd = DBProvider.CreateCommand())
{
cmd.Connection = conn;
cmd.CommandText = string.Format("select * from {0}", tableNmae).ToUpper();
try
{
DbCommandBuilder cb = DBProvider.CreateCommandBuilder();
DbDataAdapter adapter = DBProvider.CreateDataAdapter();
cb.DataAdapter = adapter;
adapter.SelectCommand = cmd;
DbCommand cmdinsert = cb.GetInsertCommand();
DbCommand cmdupdate = cb.GetUpdateCommand();
DbCommand cmddelete = cb.GetDeleteCommand();
adapter.InsertCommand = cmdinsert;
adapter.UpdateCommand = cmdupdate;
adapter.DeleteCommand = cmddelete;
adapter.TableMappings.Add("Table", ds.Tables[0].TableName);
int num = adapter.Update(ds);
return num;
}
catch (DbException ex)
{
conn.Close();
conn.Dispose();
throw new Exception(ex.Message);
}
}
}
}
#endregion
#region 存储过程操作
/// <summary>
/// 执行存储过程;
/// </summary>
/// <param name="storeProcName">存储过程名</param>
/// <param name="parameters">所需要的参数</param>
/// <returns>返回受影响的行数</returns>
public int RunProcedureNonQuery(string storeProcName, DbParameter[] parameters)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
DbCommand cmd = BuildQueryCommand(conn, storeProcName, parameters);
int rows = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
conn.Close();
return rows;
}
}
/// <summary>
/// 执行存储过程,返回首行首列的值
/// </summary>
/// <param name="storeProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <returns>返回首行首列的值</returns>
public Object RunProcedureScalar(string storeProcName, DbParameter[] parameters)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
try
{
DbCommand cmd = BuildQueryCommand(conn, storeProcName, parameters);
object obj = cmd.ExecuteScalar();
cmd.Parameters.Clear();
if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch (DbException e)
{
conn.Close();
conn.Dispose();
throw new Exception(e.Message);
}
}
}
/// <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 DbDataReader RunProcedureReader(string storedProcName, DbParameter[] parameters)
{
DbConnection conn = DBProvider.CreateConnection();
conn.ConnectionString = DBConnectionString;
DbDataReader returnReader;
DbCommand cmd = BuildQueryCommand(conn, storedProcName, parameters);
cmd.CommandType = CommandType.StoredProcedure;
returnReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return returnReader;
}
/// <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>DataSet</returns>
public DataSet RunProcedureQuery(string storedProcName, DbParameter[] parameters)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
DataSet dataSet = new DataSet();
DbDataAdapter sqlDA = DBProvider.CreateDataAdapter();
sqlDA.SelectCommand = BuildQueryCommand(conn, storedProcName, parameters);
sqlDA.Fill(dataSet);
sqlDA.SelectCommand.Parameters.Clear();
sqlDA.Dispose();
return dataSet;
}
}
/// <summary>
/// 执行多个存储过程，实现数据库事务。
/// </summary>
/// <param name="SQLStringList">存储过程的哈希表（value为存储过程语句，key是该语句的DbParameter[]）</param>
public bool RunProcedureTran(Hashtable SQLStringList)
{
using (DbConnection conn = DBProvider.CreateConnection())
{
conn.ConnectionString = DBConnectionString;
conn.Open();
using (DbTransaction trans = conn.BeginTransaction())
{
using (DbCommand cmd = DBProvider.CreateCommand())
{
try
{
//循环
foreach (DictionaryEntry myDE in SQLStringList)
{
cmd.Connection = conn;
string storeName = myDE.Value.ToString();
DbParameter[] cmdParms = (DbParameter[])myDE.Key;
cmd.Transaction = trans;
cmd.CommandText = storeName;
cmd.CommandType = CommandType.StoredProcedure;
if (cmdParms != null)
{
foreach (DbParameter parameter in cmdParms)
{
cmd.Parameters.Add(parameter);
}
}
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
}
trans.Commit();
return true;
}
catch
{
trans.Rollback();
conn.Close();
conn.Dispose();
return false;
}
}
}
}
}
#endregion
}
}