数据操作层的基类,主要封装了数据的增,删,改,查功能

using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.Common ;
using System.Data.OleDb;

namespace DataAccess
{
/// <summary>
/// 数据操作层的基类,主要封装了数据的增,删,改,查功能
/// </summary>
public abstract class BaseAccess
{
#region 私有和保护成员

protected DbManager _DbManager = null; // 数据库连接对象
protected string _TableName = string.Empty ; // 表名
protected string _PKName = string.Empty ; // 主键字段名

#endregion

#region 私有属性
/// <summary>
/// 基本SELECT SQL语句
/// </summary>
protected string SelectSql
{
get
{
return string.Format("SELECT * FROM [{0}] " ,_TableName) ;

}
}
#endregion

#region 构造函数

/// <summary>
/// 构造方法
/// </summary>
/// <param name="objDbManager">访问管理器</param>
public BaseAccess(DbManager objDbManager)
{
this._DbManager = objDbManager;
}
#endregion

#region 公共属性

/// <summary>
/// 当前活动数据库连接对象
/// </summary>
public SqlConnection CurrentConnection
{
get
{
return this._DbManager.CurrentConnection;

}

}

/// <summary>
/// 当前活动事务对象
/// </summary>
public SqlTransaction CurrentTransaction
{
get
{
return this._DbManager.CurrentTransaction ;
}
}

#endregion

#region 公共方法
/// <summary>
/// 数据库更新方法
/// </summary>
/// <param name="objDataSet">数据集</param>
/// <returns>返回更新行数</returns>
public int Update(string strSql)
{
return ExecuteSql(strSql);
}

/// <summary>
/// 数据库插入方法
/// </summary>
/// <param name="strSql">插入SQL语句</param>
/// <returns>返回插入的行</returns>
public int Insert(string strSql)
{
return ExecuteSql(strSql);
}

/// <summary>
/// 查询全部数据方法
/// </summary>
/// <param name="objDataSet">返回数据集</param>
/// <returns>返回查询行数</returns>
public int QueryAll(ref DataSet objDataSet)
{
SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter(SelectSql,CurrentConnection );

if(this.CurrentTransaction != null)
{
objSqlDataAdapter.SelectCommand.Transaction = CurrentTransaction;
}

return objSqlDataAdapter.Fill (objDataSet,_TableName);
}

/// <summary>
/// 查询全部数据方法
/// </summary>
/// <param name="objDataSet">返回数据集</param>
/// <returns>返回查询行数</returns>
public int QueryAll(ref DataTable objDataTable)
{
SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter(SelectSql,CurrentConnection );

if(this.CurrentTransaction != null)
{
objSqlDataAdapter.SelectCommand.Transaction = CurrentTransaction;
}
DataSet ds = new DataSet();
int nRows = objSqlDataAdapter.Fill (ds,_TableName);
objDataTable = ds.Tables[0];
return nRows;
}

/// <summary>
/// 得到ID对应的数据
/// </summary>
/// <param name="objDataSet">返回数据集</param>
/// <param name="ID">主键值</param>
/// <returns>返回查询行数</returns>
public int QueryByID(ref DataSet objDataSet,int ID)
{
string strSql = string.Format("SELECT * FROM {0} WHERE {1} = {2}", _TableName, _PKName, ID) ;

SqlCommand objCommand = new SqlCommand (strSql);

objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction != null)
{
objCommand.Transaction = CurrentTransaction;
}

SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter();
objSqlDataAdapter.SelectCommand = objCommand;

return objSqlDataAdapter.Fill(objDataSet,_TableName);

}

/// <summary>
/// 得到ID对应的数据
/// </summary>
/// <param name="objDataSet">返回数据集</param>
/// <param name="ID">主键值</param>
/// <returns>返回查询行数</returns>
public int QueryByID(ref DataTable objDataTable,int ID)
{
string strSql = string.Format("SELECT * FROM {0} WHERE {1} = {2}", _TableName, _PKName, ID) ;

SqlCommand objCommand = new SqlCommand (strSql);

objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction != null)
{
objCommand.Transaction = CurrentTransaction;
}

SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter();
objSqlDataAdapter.SelectCommand = objCommand;

DataSet ds = new DataSet();
int nRows = objSqlDataAdapter.Fill (ds,_TableName);
objDataTable = ds.Tables[0];
return nRows;

}

/// <summary>
/// 得到ID对应的数据
/// </summary>
/// <param name="objDataSet">返回数据集</param>
/// <param name="ID">主键值</param>
/// <returns>返回查询行数</returns>
public int QueryByID(ref DataSet objDataSet,string ID)
{
string strSql = string.Format("{0} WHERE {1} = '{2}'", SelectSql, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand (strSql);
objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction != null)
{
objCommand.Transaction = CurrentTransaction;
}

SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter();
objSqlDataAdapter.SelectCommand = objCommand;

return objSqlDataAdapter.Fill (objDataSet,_TableName);

}

/// <summary>
/// 得到ID对应的数据
/// </summary>
/// <param name="objDataSet">返回数据集</param>
/// <param name="ID">主键值</param>
/// <returns>返回查询行数</returns>
public int QueryByID(ref DataTable objDataTable,string ID)
{
string strSql = string.Format("{0} WHERE {1} = '{2}'", SelectSql, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand (strSql);
objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction != null)
{
objCommand.Transaction = CurrentTransaction;
}

SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter();
objSqlDataAdapter.SelectCommand = objCommand;

DataSet ds = new DataSet();
int nRows = objSqlDataAdapter.Fill (ds,_TableName);
objDataTable = ds.Tables[0];
return nRows;

}

/// <summary>
/// 用SQL查询数据
/// </summary>
/// <param name="objDataSet">返回数据集</param>
/// <param name="strWhere">SQL语句(WHERE 以后部分)</param>
/// <returns>返回查询行数</returns>
public int QueryByWhere(ref DataSet objDataSet,string strWhere)
{
SqlCommand objCommand = new SqlCommand (SelectSql + " WHERE " + strWhere);
objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction != null)
{
objCommand.Transaction = CurrentTransaction;
}

SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter() ;
objSqlDataAdapter.SelectCommand = objCommand ;

return objSqlDataAdapter.Fill (objDataSet,_TableName);

}

/// <summary>
/// 用SQL查询数据
/// </summary>
/// <param name="objDataSet">返回数据集</param>
/// <param name="strWhere">SQL语句(WHERE 以后部分)</param>
/// <returns>返回查询行数</returns>
public int QueryByWhere(ref DataTable objDataTable,string strWhere)
{
SqlCommand objCommand = new SqlCommand (SelectSql + " WHERE " + strWhere);
objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction != null)
{
objCommand.Transaction = CurrentTransaction;
}
DataSet ds = new DataSet();
SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter() ;
objSqlDataAdapter.SelectCommand = objCommand ;

int nRows = objSqlDataAdapter.Fill(ds,_TableName);
objDataTable = ds.Tables[0];
return nRows;

}

/// <summary>
/// 用SQL查询数据
/// </summary>
/// <param name="dataSet">返回数据集</param>
/// <param name="strSql">整个SQL语句</param>
/// <returns>返回查询行数</returns>
public int QueryBySql(ref DataSet dataSet ,string strSql)
{
SqlCommand objCommand = new SqlCommand (strSql);

objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction != null)
{
objCommand.Transaction = CurrentTransaction;
}

SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter();
objSqlDataAdapter.SelectCommand = objCommand ;

return objSqlDataAdapter.Fill (dataSet,_TableName);

}

/// <summary>
/// 用SQL查询数据
/// </summary>
/// <param name="objTable">返回数据集</param>
/// <param name="strSql">整个SQL语句</param>
/// <returns>返回查询行数</returns>
public int QueryBySql(ref DataTable objTable ,string strSql)
{
SqlCommand objCommand = new SqlCommand (strSql);

objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction != null)
{
objCommand.Transaction = CurrentTransaction;
}

SqlDataAdapter objSqlDataAdapter = new SqlDataAdapter();
objSqlDataAdapter.SelectCommand = objCommand ;
DataSet ds = new DataSet() ;

int nRows = objSqlDataAdapter.Fill(ds,_TableName);
objTable = ds.Tables[0] ;
return nRows ;

}

/// <summary>
/// 删除数据
/// </summary>
/// <param name="strSql">删除SQL语句</param>
/// <returns>删除行数</returns>
public int DeleteData(string strSql)
{
return ExecuteSql(strSql);
}

/// <summary>
/// 更新scType为1
/// </summary>
/// <param name="ID"> 主键ID</param>
/// <returns>返回更新行</returns>
public int UpdateScType(int ID)
{
string strSql = string.Format("UPDATE {0} set scType=1 WHERE {1} = {2}", _TableName, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;
}

/// <summary>
/// 更新scType为1
/// </summary>
/// <param name="ID"> 主键ID</param>
/// <returns>返回更新行</returns>
public int UpdateScType(string ID)
{
string strSql = string.Format("UPDATE {0} set scType=1 WHERE {1} = '{2}'", _TableName, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;
}

/// <summary>
/// 更新State状态
/// </summary>
/// <param name="strFieldName">字段名</param>
/// <param name="strText">更新值</param>
/// <param name="ID">主键ID</param>
/// <returns>返回更新行</returns>
public int UpdateState(string strFieldName,int intText,string ID)
{
string strSql = string.Format("UPDATE {0} set {1}={2} WHERE {3} = '{4}'", _TableName,strFieldName,intText, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;
}

/// <summary>
/// 更新State状态
/// </summary>
/// <param name="strFieldName">字段名</param>
/// <param name="strText">更新值</param>
/// <param name="ID">主键ID</param>
/// <returns>返回更新行</returns>
public int UpdateState(string strFieldName,string strText,string ID)
{
string strSql = string.Format("UPDATE {0} set {1}='{2}' WHERE {3} = '{4}'", _TableName,strFieldName,strText, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;
}

/// <summary>
/// 更新State状态
/// </summary>
/// <param name="strFieldName">字段名</param>
/// <param name="strText">更新值</param>
/// <param name="ID">主键ID</param>
/// <returns>返回更新行</returns>
public int UpdateState(string strFieldName,string strText,string strFieldName2, string ID)
{
string strSql = string.Format("UPDATE {0} set {1}='{2}' WHERE {3} = '{4}'", _TableName,strFieldName,strText, strFieldName2, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;
}

/// <summary>
/// 更新State状态
/// </summary>
/// <param name="strFieldName">字段名</param>
/// <param name="strText">更新值</param>
/// <param name="ID">主键ID</param>
/// <returns>返回更新行</returns>
public int UpdateState(string strFieldName,int intText,string strFieldName2, int ID)
{
string strSql = string.Format("UPDATE {0} set {1}={2} WHERE {3} = {4}", _TableName,strFieldName,intText, strFieldName2, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;
}

/// <summary>
/// 更新State状态
/// </summary>
/// <param name="strFieldName">字段名</param>
/// <param name="strText">更新值</param>
/// <param name="ID">主键ID</param>
/// <returns>返回更新行</returns>
public int UpdateState(string strFieldName,string strText,int ID)
{
string strSql = string.Format("UPDATE {0} set {1}='{2}' WHERE {3} = {4}", _TableName,strFieldName,strText, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;
}

/// <summary>
/// 更新State状态
/// </summary>
/// <param name="strFieldName">字段名</param>
/// <param name="strText">更新值</param>
/// <param name="ID">主键ID</param>
/// <returns>返回更新行</returns>
public int UpdateState(string strFieldName,int intText,int ID)
{
string strSql = string.Format("UPDATE {0} set {1}={2} WHERE {3} = {4}", _TableName,strFieldName,intText, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;
}

/// <summary>
/// 删除数据库中ID对应数据
/// </summary>
/// <param name="ID">对象ID</param>
/// <returns>删除行数</returns>
public int Delete(int ID)
{
string strSql = string.Format("DELETE FROM {0} WHERE {1} = {2}", _TableName, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand(strSql) ;
objCommand.Connection = CurrentConnection ;
if(CurrentTransaction != null)
{
objCommand.Transaction =CurrentTransaction ;
}
return objCommand.ExecuteNonQuery() ;

}

/// <summary>
/// 删除数据库中ID对应数据
/// </summary>
/// <param name="ID">对象ID</param>
/// <returns>删除行数</returns>
public int Delete(string ID)
{
string strSql = string.Format("DELETE FROM {0} WHERE {1} = '{2}'", _TableName, _PKName, ID) ;
SqlCommand objCommand = new SqlCommand(strSql);
objCommand.Connection = CurrentConnection;
if(CurrentTransaction !=null)
{
objCommand.Transaction =CurrentTransaction;
}
return objCommand.ExecuteNonQuery();

}

/// <summary>
/// 执行SQL语句
/// </summary>
/// <param name="strSql"></param>
/// <returns>所影响数据库记录的行数</returns>
public int ExecuteSql(string strSql)
{
try
{
SqlCommand objCmd = new SqlCommand(strSql) ;

objCmd.Connection = this.CurrentConnection ;
if(CurrentTransaction != null)
{
objCmd.Transaction = CurrentTransaction ;
}
return objCmd.ExecuteNonQuery() ;
}
catch(Exception ex)
{
string strTemp = ex.Message;
return -1;
}
}

/// <summary>
/// 获取当前一个唯一标识,插入记录后用此函数获取系统自动生成的ID值
/// </summary>
/// <returns></returns>
public int GetCurIdentity()
{
string strSql=string.Format("SELECT IDENT_CURRENT('{0}')", _TableName) ;
SqlCommand objCommand = new SqlCommand (strSql);

objCommand.Connection = CurrentConnection;
if(this.CurrentTransaction !=null)
{
objCommand.Transaction =CurrentTransaction;
}

object objValue=objCommand.ExecuteScalar();
return int.Parse(objValue.ToString());

}

/// <summary>
/// 获取下一个种子值
/// </summary>
/// <returns></returns>
public int GetNextSeed()
{
DbManager objManager = new DbManager();

try
{
string strSql = string.Format("SELECT iCount FROM tblAutoIncrease WHERE tblName = '{0}' and fieldName='{1}'", _TableName,_PKName) ;
SqlCommand objCommand = new SqlCommand (strSql);
objCommand.Connection = objManager.CurrentConnection;
object objValue=objCommand.ExecuteScalar() ; // 暂无种子值
int intReturn = 1 ;
if(objValue == null)
{
strSql = string.Format("INSERT INTO tblAutoIncrease(tblName,fieldName,iCount) VALUES('{0}', '{1}',2)", _TableName,_PKName) ;
}
else
{
intReturn = int.Parse(objValue.ToString()) ;
strSql += string.Format("UPDATE tblAutoIncrease SET iCount = {0} WHERE tblName = '{1}'", intReturn + 1, _TableName) ;
}

// 更新种子值
objCommand.CommandText = strSql ;
objCommand.ExecuteNonQuery() ;
return intReturn ;
}
finally
{
objManager.Dispose();
}

}

/// <summary>
/// 是否存在字段值
/// </summary>
/// <param name="strName">返回0表示不存在，返回1表示已经存在</param>
/// <returns></returns>
public int IsExistFieldValue(string strFieldName,string strFieldValue)
{
string strSql = string.Format("select count(*) from {0} where {1}='{2}' and scType=0",_TableName,strFieldName,strFieldValue);
DataTable objTable = new DataTable();
QueryBySql(ref objTable,strSql);
return Convert.ToInt32(objTable.Rows[0][0]);
}

/// <summary>
/// 是否存在字段值
/// </summary>
/// <param name="strName">返回0表示不存在，返回1表示已经存在</param>
/// <returns></returns>
public int IsExistFieldValue(string strFieldName,int intFieldValue)
{
string strSql = string.Format("select count(*) from {0} where {1}={2} and scType=0",_TableName,strFieldName,intFieldValue);
DataTable objTable = new DataTable();
QueryBySql(ref objTable,strSql);
return Convert.ToInt32(objTable.Rows[0][0]);
}

#endregion

}

}