net数据库操作类

using System;


using System.Web;


using System.Data.SqlClient;


using System.Data;


using System.Configuration;




namespace op_db




...{




/**//**//**//// <summary>


/// 专门用来处理与数据库的操作


/// </summary>


public class db_class




...{




成员成员#region 成员


private SqlConnection conn=new SqlConnection();




/**//**//**//// <summary>


/// 私有成员


/// </summary>


private string _sql;




/**//**//**//// <summary>


/// 属性：数据库查询语句


/// </summary>


private string _er;


public string er




...{




get...{return _er;}




}


public string sql




...{




get...{return _sql;}




set...{_sql=value;}


}


#endregion








函数函数#region 函数






/**//**//**//// <summary>


/// 构造函数


/// </summary>


public db_class()




...{


//


// TODO: 在此处添加构造函数逻辑


//


conn.ConnectionString=System.Configuration.ConfigurationSettings.AppSettings["constr"].ToString();


}




/**//**//**//// <summary>


/// 析构函数


/// </summary>


~ db_class()




...{


if (conn.State==ConnectionState.Open)


conn.Close();


}






/**//**//**//// <summary>


/// 打开数据库连接


/// </summary>


public void db_open()




...{


try




...{


if (conn.State==ConnectionState.Closed)




...{


conn.ConnectionString=System.Configuration.ConfigurationSettings.AppSettings["constr"].ToString();


conn.Open();


}


}


catch(Exception ex)




...{


//System.Web.HttpContext.Current.Response.Redirect(System.Configuration.ConfigurationSettings.AppSettings["conn_admin"].ToString());


System.Web.HttpContext.Current.Response.Write(ex.Message);


System.Web.HttpContext.Current.Response.End();


}




}






/**//**//**//// <summary>


/// 关闭数据库连接


/// </summary>


public void db_close()




...{




if (conn.State==ConnectionState.Open)...{


conn.Close();


conn.Dispose();


}


}








/**//**//**//// <summary>


/// 执行非返回型查询语句


/// </summary>


/// <returns>是否执行成功</returns>


public bool executesql()




...{


SqlCommand cmd=new SqlCommand(_sql,conn);


this.db_open();


try




...{


cmd.ExecuteNonQuery();


this.db_close();


return true;


}


catch(Exception ex)




...{


this.db_close();


System.Web.HttpContext.Current.Response.Write(ex.Message);


System.Web.HttpContext.Current.Response.End();


return false;


}




}






/**//**//**//// <summary>


/// 执行返回datareader的数据库查询


/// </summary>


/// <returns>datareader对象</returns>


public SqlDataReader executereader()




...{


SqlCommand cmd=new SqlCommand(_sql,conn);


this.db_open();


SqlDataReader dr;


try




...{


dr=cmd.ExecuteReader(CommandBehavior.CloseConnection);//参数表示关闭datagrid对象就会关闭connection对象


if (dr.HasRows==true)




...{


return dr;


}


else




...{


_er="数据为空";


return null;


}


}


catch




...{


_er="语句错误";


return null;


}


}








/**//**//**//// <summary>


/// 将sql语句返回为dataview


/// </summary>


/// <returns>dataview对象</returns>


public DataView executedv()




...{


System.Data.SqlClient.SqlDataAdapter da=new SqlDataAdapter(_sql,conn);


DataSet ds=new DataSet();


this.db_open();


try




...{


da.Fill(ds,"tb");


DataView dv=new DataView(ds.Tables["tb"]);


if (dv.Count>0)




...{


this.db_close();


return dv;


}


else




...{


this.db_close();


_er="数据出错";


return null;


}


}


catch




...{


_er="数据出错";


return null;


}


finally




...{


this.db_close();


}


}






/**//**//**//// <summary>


/// 将只返回一条记录的sql语句执行并且返回结果


/// </summary>


/// <param name="def">如果没有记录的话的默认值</param>


/// <returns>返回结果为string</returns>




public string sql2str(string def)




...{


string rr="";


SqlCommand cmd=new SqlCommand(_sql,conn);


System.Data.SqlClient.SqlDataReader dr;


this.db_open();


try




...{


dr=cmd.ExecuteReader(CommandBehavior.CloseConnection);


if(dr.HasRows)




...{


dr.Read();


rr=dr[0].ToString();


dr.Close();


this.db_close();


}


}


catch




...{


rr="";


}




finally...{this.db_close();}


if(rr=="")


rr=def;


return rr;


}








/**//**//**//// <summary>


/// 执行返回BOOL的存储过程


/// </summary>


/// <returns>是否执行成功</returns>


public bool exepro()




...{


this.db_open();


SqlCommand cmd=new SqlCommand(_sql,conn);


cmd.CommandType=CommandType.StoredProcedure;


try




...{


cmd.ExecuteNonQuery();


this.db_close();


return true;


}


catch




...{


this.db_close();


return false;


}




}


#endregion


}


}